Digoxin

Digoxin is a familiar heart medication in the book’s hospital settings, but its routine presence also makes it useful to Charles Cullen as a concealed poison. Known among nurses as didge and commonly abbreviated to dig on charts, it appears first as a drug handled within ordinary clinical procedures, then as a substance detected in patients at alarming levels. Its recurrence connects distinct patient cases and gives investigators a concrete chemical clue, while the difficulty of proving who administered it shows how far evidence of access can remain from proof of a killing.

Clinical Use and Access

Digoxin is kept in small glass ampules in a hospital drug closet, loaded into a plastic drawer called a cassette. It is common in the ICU and used to slow the firing mechanism of heart muscles. On a chart, its name can be reduced to the brief notation dig; that shorthand reflects its familiarity in the workplace, but also makes its movement harder to distinguish from the flow of routine care.

The book makes the drug’s ordinary appearance part of its concealment. Digoxin is clear, like saline, and can be introduced into an IV line through the piggyback port, an access point nurses routinely use to flush a line. The action can therefore resemble legitimate care. A private room and the expectation of one-on-one attention further reduce the chance that an injection will be seen. These details explain the opportunity the drug affords without making the medication itself suspicious: the same access and routines that support treatment can hide tampering.

The dose details sharpen the contrast between medical use and poisoning. Jin Kyung Han had received 0.125 mg doses on June 12 and June 13, with a reported therapeutic blood level of about 0.63. A later account identifies a unit as 2 cc, or 0.5 mg. At Warren Hospital, Cullen loaded three ampules, calculating a total of 1.5 mg and considering whether that amount could be sufficient if given intramuscularly. The book records his preparation and his walk into the patient’s room, but does not establish the exact amount or route used in every subsequent poisoning.

Early Deaths and the Unrecognized Pattern

After Cullen injected Helen Dean, she became violently ill the next day: she was sweating and exhausted, and her heart stopped. Attempts to revive her failed. Cullen returned to work and was questioned by doctors, Warren administrators, nurse supervisors, and investigators from the Warren County Prosecutor’s Office. He denied the injection while his locker was searched. The medical examiner sampled a small injection site on Dean’s thigh and tested for nearly one hundred potentially lethal chemicals, but digoxin was not among them. Her death was classified as natural causes. The missed test left a potentially decisive clue unrecognized.

A later case supplied a different kind of signal. Ottomar Schramm’s longtime general practitioner called his daughter, Kristina Toth, after unauthorized blood tests at the hospital found digoxin in Schramm’s blood, although he had never been prescribed it. The level was described as off the charts. A follow-up test confirmed the result, and the doctor called again at 1:25 a.m. to report that Schramm was dead. Here, laboratory evidence disclosed the drug’s presence, but the account of the tests alone did not identify who had administered it.

On August 31, 1999, Cullen loaded Matthew Mattern’s IV with a bolus dose of digoxin. Mattern’s slow code ended before sunrise, and some nurses interpreted the death as an instance of divine intervention. The medication’s presence in an IV made the act part of the clinical environment rather than an obviously separate assault; the routine vocabulary of care could obscure the intervention even as it caused a death.

Somerset: A Survivor and a Fatal Case

By June 2003, the pattern included patients whose digoxin levels could be compared with their prescriptions and charted care. Jin Kyung Han had arrived at the hospital on June 12 with Hodgkin’s lymphoma and heart disease. Her cardiologist had prescribed small doses, ordinarily 0.125 mg, but after reviewing her electrocardiogram on June 13, he concluded that digoxin was not helping her new arrhythmias and might kill her. He ordered it discontinued.

On June 14, Cullen arrived half an hour early and reviewed computerized patient charts before selecting Han, who was not his patient. Her heart rate later plunged, she vomited during the morning shift, and a blood screen showed that her digoxin level had risen from its usual 0.63 to 9.94. Her cardiologist ordered an antidote. Han stabilized, remained unwell through the day and night shifts, but survived. Her case made the discrepancy between a discontinued prescription and a sharply elevated level especially consequential: the drug was no longer an appropriate treatment for her, yet it was present in her system at a dangerous concentration.

Reverend Florian Gall’s case became the central forensic test of the drug’s evidentiary value. He went into cardiac arrest at approximately 9:32 a.m. on June 28. Resuscitation efforts failed, and his time of death was recorded as 10:10 a.m. His bloodwork showed digoxin at an exceptionally high level. After his body was exhumed, toxicology found the drug in several tissues: 23.4 mcg/l in the vitreous fluid, 32.0 mcg/kg in the spleen, 40.8 mcg/kg in the heart, and 104 mcg/kg in the kidney. Those results allowed Nobby C. Mambo to amend the cause of death to digoxin toxicity and the manner of death to homicide. Investigators now had both a murder victim and a murder weapon, but not yet a sure way to prove who had used it.

From Chemical Finding to Investigative Evidence

Gall’s death prompted hospital staff to examine the drug’s access history and the timing of abnormal laboratory values. The review focused on Gall and Han, and included Pyxis reports, canceled drug orders, and access to digoxin in the Critical Care unit. Pharmacy was asked to contact Poison Control to determine what dose might produce a serum level of 9, the level reported in Gall’s bloodwork. The inquiry joined the biological evidence to medication records, but it did not make either record self-explanatory: a test could establish exposure, while a system entry could show access without proving administration.

The police investigation encountered the same distinction. Cullen’s Pyxis records showed requests and cancellations for digoxin on June 15 and June 27. Investigators could use those entries alongside Cerner printouts and Gall’s toxicology to show that Cullen could have obtained the drug. Prosecutor Wayne Forrest recognized that possibility was not proof. Cullen could claim that medication orders were valid, and cancellations could be dismissed as mistakes. Even a suspicious pattern across records could not, by itself, establish that he had injected Gall.

The missing-vial problem made the gap more tangible. In the hospital’s internal review, records showed that several vials of digoxin had not been accounted for during the previous month. Staff agreed to monitor patients in the ICU and CCU carefully and to treat digoxin orders or administrations as warning signs. Yet the same review concluded that the available records and Cullen’s demeanor were not overtly suspicious enough to warrant contacting authorities. Digoxin had become a reason for vigilance, but the response remained bounded by uncertainty about what the records could prove.

Significance

Digoxin’s role in the narrative depends on a tension between familiarity and danger. It is ordinary enough to be stocked, abbreviated, and handled through routine procedures; it is also potent enough that abnormal levels can turn an unexplained collapse into a suspected poisoning, and forensic testing can reclassify a death as homicide. The cases do not all resolve in the same way: Helen Dean’s death was ruled natural after digoxin was omitted from testing, Han survived after an antidote, and Gall’s tissue samples established the cause and manner of death without conclusively identifying the killer.

The drug therefore functions as both a means of harm and an evidentiary thread. Its clear appearance and legitimate routes of administration help explain how an intervention could pass for care. Its laboratory signature, on the other hand, gives investigators a basis for connecting otherwise separate medical crises. The book’s central distinction is that finding digoxin in a patient can establish exposure, and finding it in a record can establish an opportunity, while neither fact alone necessarily proves the act of murder.