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WebM&M: Case Studies

WebM&M (Morbidity & Mortality Rounds on the Web) features expert analysis of medical errors reported anonymously by our readers. Spotlight Cases include interactive learning modules available for CME. Commentaries are written by patient safety experts and published monthly.

Have you encountered medical errors or patient safety issues? Submit your case below to help the medical community and to prevent similar errors in the future.

This Month's WebM&Ms

Update Date: November 16, 2022
Nasim Hedayati, MD, and Richard White, MD | November 16, 2022

A 61-year-old women with a mechanical aortic valve on chronic warfarin therapy was referred to the emergency department (ED) for urgent computed tomography (CT) imaging of the right leg to rule out an arterial clot. CT imaging revealed two... Read More

Leilani Schweitzer | November 16, 2022

A 58-year-old man underwent a complex surgery to replace his aortic value. The surgery required prolonged cardiopulmonary bypass time and cross-clamp time and there was a short delay in redosing the cardioplegic solution and the patient developed ... Read More

Have you encountered medical errors or patient safety issues?
Have you encountered medical errors or patient safety issues? Submit your case below to help the medical community and to prevent similar errors in the future.

All WebM&M: Case Studies (376)

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Displaying 1 - 20 of 376 WebM&M Case Studies
Nasim Hedayati, MD, and Richard White, MD| November 16, 2022

A 61-year-old women with a mechanical aortic valve on chronic warfarin therapy was referred to the emergency department (ED) for urgent computed tomography (CT) imaging of the right leg to rule out an arterial clot. CT imaging revealed two arterial thromboses the right lower extremity and an echocardiogram revealed a thrombus near the prosthetic heart valve. The attending physician ordered discontinuation of warfarin and initiation of a heparin drip. On hospital day 3, the patient’s right leg became discolored and cold, but the healthcare team insisted that she was being treated appropriately; two days later, the patient complained of pain, additional discoloration, and her toes appeared to be turning black. The patient was taken to the Operating Room (OR) to remove the arterial thrombus, but a more extensive operation was needed to restore arterial blood flow. The commentary summarizes the signs of acute limb ischemia and appropriate approaches to prevent and manage arterial thrombosis, particularly among patients on anticoagulants.

A 49-year-old woman presented to an Emergency Department (ED) with abdominal pain nine hours after discharge following outpatient laparoscopic left oophorectomy. The left oophorectomy procedure involved an umbilical port placed using an Optiport visual trocar, a suprapubic port, and two additional ports laterally. The operative note mentioned no visible injury upon entry into the abdominal cavity, but there were extensive adhesions in the pelvis. Nine hours after discharge, the patient presented to another hospital due to increasing pain, nausea, and fever. The patient underwent a laparotomy and the surgical team found fecal contamination upon entry into the peritoneal cavity; the surgeons concluded that the most plausible explanation was a trocar injury. The commentary discusses the risk of vascular and bowel injury during peritoneal access for laparoscopy and the importance of patient history and abdominal anatomy when considering approaches to abdominal entry.

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A 65-year-old female with a documented allergy to latex underwent surgery for right-sided Zenker’s diverticulum. Near the conclusion of surgery, a latex Penrose drain was placed in the neck surgical incision. The patient developed generalized urticaria, bronchospasm requiring high airway pressures to achieve adequate ventilation, and hypotension within 5 minutes of placement of the drain. The drain was removed and replaced with a silicone drain. Epinephrine and vasopressors were administered post-operatively and the patient’s symptoms resolved. The commentary discusses risk factors and consequences of latex allergy in hospital and operating room settings, common latex products that trigger allergic reactions  and hospital safety practices that can limit the risk of latex exposure.

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Anamaria Robles, MD, and Garth Utter, MD, MSc | August 31, 2022

A 49-year-old woman was referred by per primary care physician (PCP) to a gastroenterologist for recurrent bouts of abdominal pain, occasional vomiting, and diarrhea. Colonoscopy, esophagogastroduodenoscopy, and x-rays were interpreted as normal, and the patient was reassured that her symptoms should abate. The patient was seen by her PCP and visited the Emergency Department (ED) several times over the next six months. At each ED visit, the patient’s labs were normal and no imaging was performed. A second gastroenterologist suggested a diagnosis of intestinal ischemia to the patient, her primary gastroenterologist, her PCP, and endocrinologist but the other physicians did not follow up on the possibility of mesenteric ischemia. On another ED visit, the second gastroenterologist consulted a surgeon, and a mesenteric angiogram was performed, confirming a diagnosis of mesenteric ischemia with gangrenous intestines. The patient underwent near-total intestinal resection, developed post-operative infections requiring additional operations, experienced cachexia despite parenteral nutrition, and died of sepsis 3 months later.  The commentary discusses the importance of early diagnosis of mesenteric ischemia and how to prevent diagnostic errors that can impede early identification and treatment.

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Samson Lee, PharmD, and Mithu Molla, MD, MBA| August 5, 2022

This WebM&M highlights two cases where home diabetes medications were not reviewed during medication reconciliation and the preventable harm that could have occurred. The commentary discusses the importance of medication reconciliation, how to compile the ‘best possible medication history’, and how pharmacy staff roles and responsibilities can reduce medication errors.

Kevin J. Keenan, MD, and Daniel K. Nishijima, MD, MAS | July 8, 2022

A 58-year-old man with a past medical history of seizures presented to the emergency department (ED) with acute onset of left gaze deviation, expressive aphasia, and right-sided hemiparesis. The patient was evaluated by the general neurology team in the ED, who suspected an acute ischemic stroke and requested an evaluation by the stroke neurology team but did not activate a stroke alert. The stroke team concluded that the patient had suffered a focal seizure prior to arrival and had postictal deficits. The stroke team did not order emergent CT angiography and perfusion imaging but recommended routine magnetic resonance imaging with angiography (MRI/MRA) for further evaluation, which showed extensive cerebral infarction in the distribution of an occluded left middle cerebral artery (MCA). Due to the delayed diagnosis of left MCA stroke, it was too late to perform any neurovascular intervention. The commentary highlights the importance of timely use of stroke alert protocols, challenges with CT angiography in early acute ischemic stroke, and the importance of communication and collaboration between ED and neurology teams.

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Garima Agrawal, MD, MPH, and Mithu Molla, MD, MBA | May 16, 2022

This WebM&M describes two cases involving patients who became unresponsive in unconventional locations – inside of a computed tomography (CT) scanner and at an outpatient transplant clinic – and strategies to ensure that all healthcare teams are prepared to deliver advanced cardiac life support (ACLS), such as the use of mock codes and standardized ACLS algorithms.

John Landefeld, MD, MS, Sara Teasdale, MD, and Sharad Jain, MD| February 23, 2022

A 65-year-old woman with a history of 50 pack-years of cigarette smoking presented to her primary care physician (PCP), concerned about lower left back pain; she was advised to apply ice and take ibuprofen. She returned to her PCP a few months later reporting persistent pain. A lumbar spine radiograph showed mild degenerative disc disease and the patient was prescribed hydrocodone/acetaminophen in addition to ibuprofen. In the following months, she was seen by video twice for progressive, more severe pain that limited her ability to walk. A year after the initial evaluation, the patient presented to the Emergency Department (ED) with severe pain. X-rays showed a 5 cm lesion in her lung, a small vertebral lesion and multiple lesions in her pelvic bones. A biopsy led to a diagnosis of lung cancer and magnetic resonance imaging (MRI) showed metastases to the liver and bone, as well as multiple small fractures of the pelvic girdle. Given the extent of metastatic disease, the patient decided against aggressive treatment with curative intent and enrolled in hospice; she died of metastatic lung cancer 6 weeks after her enrollment in hospice. The commentary summarizes the ‘red flag’ symptoms associated with low back pain that should prompt expedited evaluation, the importance of lung cancer screening for patients with a history of heavy smoking, and how pain-related stigma can contribute to contentious interactions between providers and patients that can limit effective treatment.

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Nandakishor Kapa, M.D., and José A. Morfín, M.D.| February 23, 2022

A 69-year-old man with End-Stage Kidney Disease (ESKD) secondary to diabetes mellitus and hypertension, who had been on dialysis since 2014, underwent deceased donor kidney transplant. The case demonstrates the complex nature of management of allograft dysfunction due to vascular complications in a patient with deceased donor kidney transplant in the early post-transplant period. The commentary discusses how standardized follow-up imaging protocols can support early recognition and evaluation of allograft dysfunction due to vascular complications in kidney transplant recipients, as well the importance of team communication for patients requiring multiple interventions to reduce lag time in addressing further complications.

This case involves a 2-year-old girl with acute myelogenous leukemia and thrombocytopenia (platelet count 26,000 per microliter) who underwent implantation of a central venous catheter with a subcutaneous port. The anesthetist asked the surgeon to order a platelet transfusion to increase the child’s platelet count to above 50,000 per microliter. In the post-anesthesia care unit, the patient’s arterial blood pressure started fluctuating and she developed cardiac arrest. A “code blue” was called and the child was successfully resuscitated after insertion of a thoracostomy drainage (chest) tube. Unfortunately, the surgeon damaged an intercostal artery when he inserted the chest tube emergently, which caused further bleeding and two additional episodes of PEA arrest. This commentary addresses the importance of mitigating risk during procedures, balancing education of proceduralist trainees with risk to the patient, and prompt review of diagnostic studies by qualified individuals to identify serious complications.

Robin Aldwinckle, MD and Edmund Florendo, MD| October 27, 2021

A 78-year-old woman with macular degeneration presented for a pars plana vitrectomy (PPV) under monitored anesthesia care (MAC) with an eye block. At this particular hospital, eye cases under MAC are typically performed with an eye block by the surgeon after the anesthesiologist has administered some short-acting sedation, commonly with remifentanil. On this day, there was a shortage of premixed remifentanil and the resident – who was unfamiliar with the process of drug dilution – incorrectly diluted the remifentanil solution. Shortly after receiving sedation, the patient became unresponsive, and a code was called. The commentary addresses the challenges of drug dilution and strategies to reduce dilutional errors and prioritize patient safety.

Florence Tan, PharmD, Karnjit Johl, MD and Mariya Kotova, PharmD| September 29, 2021

This case describes multiple emergency department (ED) encounters and hospitalizations experienced by a middle-aged woman with sickle cell crisis and a past history of multiple, long admissions related to her sickle cell disease. The multiple encounters highlight the challenges of opioid prescribing for patients with chronic, non-cancer pain. The commentary discusses the limitations of prescription drug monitoring program (PDMP) data for patients with chronic pain, challenges in opioid dose conversions, and increasing patient safety through safe medication prescribing and thorough medication reconciliation.

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Linnea Lantz, DO, Joseph Yoon, MD, and David Barnes, MD, FACEP | September 29, 2021

A 44-year-old man presented to his primary care physician (PCP) with complaints of new onset headache, photophobia, and upper respiratory tract infections. He had a recent history of interferon treatment for Hepatitis C infection and a remote history of cervical spine surgery requiring permanent spinal hardware. On physical examination, his neck was tender, but he had no neurologic abnormalities. He was sent home from the clinic with advice to take over-the-counter analgesics. Over the next several days, the patient was evaluated for the same or similar symptoms again by his PCP and was seen by the emergency department and urgent care clinics before being admitted to the hospital; however, he was misdiagnosed with Staphylococcal meningitis, and it was not until his third inpatient day when cervical magnetic resonance imaging (MRI) showed a spinal epidural abscess. The commentary discusses the multiple factors leading to erroneous interpretation tests for spinal epidural abscess and the importance of broadening differentials and avoiding premature closure during diagnosis.

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Narath Carlile, MD, MPH, Soheil El-Chemaly, MD, MPH, and Gordon D. Schiff, MD | August 25, 2021

A 31-year-old woman presented to the ED with worsening shortness of breath and was unexpectedly found to have a moderate-sized left pneumothorax, which was treated via a thoracostomy tube. After additional work-up and computed tomography (CT) imaging, she was told that she had some blebs and mild emphysema, but was discharged without any specific follow-up instructions except to see her primary care physician. Three days later, the patient returned to the same ED with similar symptoms and again was found to have had a left pneumothorax that required chest tube placement, but the underlying cause was not established. After she was found two weeks later in severe respiratory distress, she was taken to another ED by paramedics where the consulting pulmonary physician diagnosed her with a rare cystic lung disease. The commentary discusses the importance of CT scans for evaluating spontaneous pneumothorax and educating providers to increase awareness of rare cystic lung diseases.

A seven-year-old girl with esophageal stenosis underwent upper endoscopy with esophageal dilation under general anesthesia. During the procedure, she was fully monitored with a continuous arterial oxygen saturation probe, heart rate monitors, two-lead electrocardiography, continuous capnography, and non-invasive arterial blood pressure measurements. The attending gastroenterologist and endoscopist were serially dilating the esophagus with larger and larger rigid dilators when the patient suddenly developed hypotension. She was immediately given a fluid bolus, phenylephrine, and 100% oxygen but still developed cardiac arrest. Cardiopulmonary resuscitation was initiated with cardiac massage, but she could not be resuscitated and died. This commentary highlights the role of communication between providers, necessary technical steps to mitigate the risks of upper endoscopy in children, and the importance of education and training for care team members.

Cynthia Li, PharmD, and Katrina Marquez, PharmD| July 28, 2021

This commentary presents two cases highlighting common medication errors in retail pharmacy settings and discusses the importance of mandatory counseling for new medications, use of standardized error reporting processes, and the role of clinical decision support systems (CDSS) in medical decision-making and ensuring medication safety.

A 52-year-old man complaining of intermittent left shoulder pain for several years was diagnosed with a rotator cuff injury and underwent left shoulder surgery. The patient received a routine follow-up X-ray four months later. The radiologist interpreted the film as normal but noted a soft tissue density in the chest and advised a follow-up chest X-ray for further evaluation. Although the radiologist’s report was sent to the orthopedic surgeon’s office, the surgeon independently read and interpreted the same images and did not note the soft tissue density or order any follow-up studies. Several months later, the patient’s primary care provider ordered further evaluation and lung cancer was diagnosed. The commentary discusses how miscommunication contributes to delays in diagnosis and treatment and strategies to facilitate effective communication between radiologists and referring clinicians.  

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David T. Martin, MD and Diane O’Leary, PhD| June 30, 2021

Beginning in her teenage years, a woman began "feeling woozy" after high school gym class. The symptoms were abrupt in onset, lasted between 5 to 15 minutes and then subsided after sitting down. Similar episodes occurred occasionally over the following decade, usually related to stress. When she was in her 30s, she experienced a more severe episode of palpitations and went to the emergency department (ED). An electrocardiogram (ECG) was normal and she was discharged with a diagnosis of stress or possible panic attack. She continued to experience these symptoms for two more years and her primary care physician (PCP) suggested that she see a psychiatrist for presumed panic attacks. At the patient’s request, the PCP ordered a 24-hour Holter monitor, which was normal. When she was 40 years old, the patient experienced another severe episode and went to the ED. During an exercise treadmill test, she experienced another “woozy” spell and the ECG showed an elevated heart rate with narrow QRS complexes. She was diagnosed with paraoxymal supraventricular tacycardia (PSVT). The commentary discusses the diagnostic challenges of PSVT and approaches to reduce diagnostic uncertainty, especially given gender bias in attributing palpitations to psychiatric rather than cardiac causes.

A 34-year-old morbidly obese man was placed under general anesthesia to treat a pilonidal abscess. Upon initial evaluation by an anesthesiologist, he was found to have a short thick neck, suggesting that endotracheal intubation might be difficult. A fellow anesthetist suggested use of video-laryngoscopy equipment, but the attending anesthesiologist rejected the suggestion. A first-year resident attempted to intubate the patient but failed. The attending anesthesiologist took over, but before intubation could be performed, the patient desaturated to 40-50%. A second attempt by the attending anesthesiologist at intubation with a glide scope also failed. The patient’s arterial saturation increased after administration of 100% oxygen by mask and he suffered no apparent neurological consequences. The commentary discusses best practices for managing high risk patients and appropriate use of advanced airway management devices.

Kelly Haas, MD, and Andrew Lee, PharmD| May 26, 2021

A 4-year-old (former 33-week premature) boy with a complex medical history including gastroschisis and subsequent volvulus in infancy resulting in short bowel syndrome, central venous catheter placement, and home parenteral nutrition (PN) dependence was admitted with hyponatremia. A pharmacist from the home infusion pharmacy notified the physician that an error in home PN mixing had been identified; a new file had been created for this chronic PN patient by the home infusion pharmacy and the PN formula in this file was transcribed erroneously without sodium acetate. This error resulted in only 20% of the patient’s prescribed sodium being mixed into the home PN solution for several weeks, resulting in hyponatremia and unnecessary hospital admission. The commentary highlights the importance of collaboration between clinicians and patients’ families for successful home PN and the roles of communication process maps, standardizing PN compounding, and order verification in reducing the risk of medication error.