Supreme Court of New York Allows Toxicology Expert Without MD To Testify In Medical Malpractice Case

Toxicology Expert Witness

Court – Supreme Court of New York
Jurisdiction – State
Case Name – Rodriguez v Pathak
Citation – 2018 N.Y. Misc. LEXIS 2830

In this medical malpractice case, it was determined that a toxicology expert witness does not need a medical degree to render an opinion on medical malpractice, so long as the expert is not making a medical diagnosis nor attesting to any medical processes or procedures.


Plaintiff Christine Rodriguez was transported to the Harlem Hospital Center (HHC) emergency department at 24 weeks gestation due to heavy vaginal bleeding and the urge to push. At the emergency department, the plaintiff reported that she had been smoking cigarettes during her pregnancy, and that she was taking antibiotics for a urinary tract infection. The plaintiff underwent an emergency Cesarean section and suffered a massive intraoperative hemorrhage that resulted in her undergoing an emergent hysterectomy. Her child, (E.A.), was placed in intense neonatal care after showing signs of early onset of pulmonary interstitial emphysema (PIE).

The infant’s condition worsened the next day and his pediatrician, Dr. Sadia Haleem, ordered 0.3 mcg of fentanyl via IV push. On the third day, attending neonatologist, Dr. Anil Pathak, first became involved with E.A.’s care. It was noted that E.A. had good chest wiggling and was moving all extremities. At 7:30 p.m., a chest x-ray was performed to place a peripherally inserted central catheter line and to ensure appropriate positioning of the endotracheal tube (ETT). A neonatal intensive care unit nurse, Olawummi Oyebola, noted that E.A. was moving frequently. At 8:15 p.m. the infant became agitated and  Dr. Pathak prescribed him with 1 mcg of fentanyl in 0.2 ml of saline.

E.A.’s father, Sebastian Armstrong, testified that while he was at E.A.’s bedside, he overheard a conversation between Dr. Pathak and a nurse in which Dr. Pathak repeatedly asked the nurse what dosage of fentanyl to give E.A. The nurse indicated that the neonatologist was administering E.A. too much medication. Mr. Armstrong also testified that Dr. Pathak thereafter squirted more of the medication out of the syringe and injected it into E.A.

At 8:35 p.m., E.A. desaturated to 68% and had bradycardia at 47 bpm and blood pressure of 29/11. Dr. Pathak further noted that E.A. had “acute deterioration” at 8:25 p.m. When the infant’s heart rate dropped into the 40s, a code was called. Dr. Pathak was at E.A.’s bedside when he was extubated, reintubated, and provided with Ambubag ventilation. Resuscitative efforts were undertaken with chest compressions and epinephrine. Despite these efforts, E.A. was pronounced dead at 8:45 p.m.

New York City Chief Medical Examiner, Dr. Candace Schoppe, performed an autopsy of E.A. and listed the cause of death as “complications of Fentanyl administration for sedation”. She noted a contributing cause of death of “extreme prematurity” and the manner of death as “therapeutic complication.” A toxicology report showed 2 ng/mL of fentanyl in E.A.’s blood and 23.6 ng/g of fentanyl in his liver.

Applying Toxicology Analysis To A Medical Malpractice Case

Before trial, the defendants argued that summary judgment must be granted because the plaintiff could not establish that defendants’ medical treatment deviated from accepted standards of care or proximately caused E.A.’s alleged injuries. In opposition, the plaintiff questioned the actual dose of fentanyl administered to E.A., and argued that the Pyxis printout, defendants’ depositions, and the written records were ambiguous and unreliable.

In support of her motion, the plaintiff retained Dr. Richard Parent, a board-certified toxicologist, who opined that while the record revealed that Dr. Pathak ordered 1 mcg of fentanyl by IV, it did not indicate what dose was actually administered. He also determined that E.A. was mistakenly dosed with 10 mcg of fentanyl based on the values from the toxicology report. In reply, the defendants attacked the credibility of plaintiff’s expert toxicologist and contended that Dr. Parent lacked a medical degree and the requisite qualifications to testify about the standard of care in the field of toxicology and/or the applicable standards of medical care.

Dr. Parent had conducted a volume of distribution (Vd) analysis, which describes how fentanyl is distributed in the body, and had calculated a Vd of 3.81 L based on E.A.’s body weight and the Vd for fentanyl (635 g x 6 L/kg). Dr. Parent explained that since fentanyl was administered to E.A. by IV, the concentration of fentanyl in E.A.’s blood could be calculated immediately after the injection was given. Dr. Parent also used the rate of clearance to calculate the concentration of fentanyl in E.A.’s blood postmortem. According to Dr. Parent, the elimination rate for fentanyl from E.A.’s body was 11.4 ml/kg/min based on the rate of clearance from the body and E.A.’s body weight (17.94 ml/kg/min x 635 g). Dr. Parent further stated that if the IV push was given 30 minutes before E.A. was pronounced dead, there would be a 9% clearance of fentanyl over a period of 30 minutes from dosing to death. Therefore, if E.A. was dosed with 1 mcg of fentanyl, he would have had an approximate blood concentration of 0.262 mcg/L or 0.262 ng/ml, nearly 8 times more than the prescribed 1 mcg dose (1 mcg/3.81 L = 0.262 mcg/L = 0.262 ng/ml).

Dr. Parent also noted that the forensic toxicology report showed 2 ng/ml of fentanyl in E.A.’s blood and 3.6 ng/g of fentanyl in his liver. Dr. Parent pointed out that c 2 ng/ml of fentanyl in E.A.’s blood was close to the range of reported fatalities in adults and 3.6 ng/g of fentanyl in his liver was within the range of reported fatalities in adults. According to Dr. Parent, what might be a borderline lethal dose of fentanyl for an adult will certainly be a lethal dose for two-day old premature infant weighing 635 g.


The court did not agree with the defendants’ assertion that plaintiff’s toxicologist was unqualified to testify on the basis that he was not a medical doctor. The court took note that Dr. Parent relied on a formulaic calculation to determine what level of toxicity is considered lethal based on an infant’s body weight and known facts about the properties of fentanyl. It was determined that the plaintiff’s toxicology expert witness did not need a medical degree to render an opinion, as he was not making a medical diagnosis nor attesting to any medical processes or procedures.

The court held that Dr. Parent had laid the proper foundation for his theories and calculations, and was satisfied that he possessed sufficient “education, training and experience from which [to] infer that his opinion would be reliable”. Furthermore, any additional medical or specialized expertise in neonatology or premature infants was deemed irrelevant and unnecessary.

The defendant’s request for summary judgment as it related to the administration of fentanyl was denied. The court held that any issues regarding  Dr. Parent’s credibility could be challenged during voir dire at trial.

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