AACE Patient Safety - Case Studies

A summer misadventure; patient safety issues during vacations because of the overconfidence of the patient

A 49 y/o drenched male with DM1 of 22 years duration was brought to the emergency department by his wife, who was also drenched. She saw him fall out of his 14 foot boat, into the water when he stood up to land a fish he caught.

Johnny’s glucose level was 122 mg% when he got into the boat, started the small outboard motor and went out into the lake. Johnny had been out on the lake for 3 hours. It was 92 degrees. He was alone in the boat, wearing his insulin pump and carrying a cell phone, “just in case he had a problem”

Johnny’s Diabetes was complicated by anesthesia in his feet with occasional sensations of intense burning, in addition to unheralded proximal muscle weakness, resulting in falls at home on 3 occasions during the previous 3 months. On this morning he ate a small breakfast, took water and his glucose tablets with him. He had left the glucose meter in his car, and did not tell his wife. He did not have a sensor with his insulin pump because it was too expensive.

Johnny said he stood up in the boat when he felt a fish on his line as he had done 4 times before, and just fell backwards, into the water. His insulin pump survived. His cell phone didn’t. “I don’t know what happened.” He said later,” I knew I was falling and there was nothing I could do about it.”

His wife, Joan, was on shore watching Johnny. She heard him hit the water and saw him splashing around until he started to swim back to the shore, towing the small boat behind him. Joan jumped into the lake to help him.

Discussion: It was a likely possibility that Johnny would fall in this situation.

  • He was at increased risk for having orthostatic hypotension in association with autonomic neuropathy,
    • He had taken his usual blood pressure medication before leaving home without lowering the dose as his physician had recommended before he goes fishing.
    • He had failed to drink enough fluids while out in the heat of the day, on the boat.
    • He had been sitting/squatting in his small boat and then stood up quickly rather than sitting on a high riser chair that might have prevented the whole event even with the other issues
  • While it is not an obvious part of the story, Johnny was at increased risk for having hypoglycemia with hypoglyemic unawareness due to autonomic neuropathy.
    • Hypoglycemic unawareness is more likely in a setting where it is hot (93 degrees) and people are sweating from the heat and intermittent increased activity while fishing or engaging in other activities.
    • He did not eat enough for breakfast.
    • He did not decrease the basal rate on his insulin pump when planning for a new, and probably energy requiring activity
    • He did not account for the increased energy requirements of getting the boat and his fishing gear ready for the day’s activity.
    • He had no way to monitor his glucose level on the boat (although that could have been a problem in itself).
Johnny did not follow his physician’s recommendations about decreasing blood pressure medications. His physician was concerned about the possibility of a fall when Johnny was on the boat. Johnny believed he would not have a problem with his fishing trip since he never had a problem before, even with the recent history of unheralded falls.

Johnny did not use the common sense one would expect from an individual trained to manage their DM1 with an insulin pump. The best thing he did was bring his wife, and that was only after an argument.

Primary Care Diabetes texts1,2 and evidence-based Endocrinology3,4 or Diabetes Care reference texts5 focus on prescription exercise programs. Patients with diabetes may interpret these as rigid recommendations and not consider intermittent activities, like an occasional fishing trip, in the same category as exercise.

Unger1 provides list of risks associated with exercise in patients with diabetic complications which include the following relevant features:

  • Impaired temperature control
  • Orthostatic hypotension
  • Dehydration
  • Difficulty maintain balance
When a patient will be physically active in 90 degree weather, a warning is necessary about the effect of high temperatures on the integrity of insulin activity and the accuracy of some glucose test strips.6

Postural mechanism deficiency, decreased lower extremity muscle strength and autonomic neuropathic symptoms may be difficult to identify in patients with Diabetes who have sensory neuropathy7,8. In Fact,..” symptoms may be absent or nonspecific, such as generalized weakness, fatigue, nausea, cognitive slowing, leg buckling, or headache.”9

This kind of misjudgment occurs when people do things they not do every day. More intensive vacation day diabetes management teaching may have prevented this occurrence. While Johnny’s physician gave him recommendations, clearly, they were not heeded. This suggests that physicians should pay close attention to vacation plans of their patients with Diabetes. We focus on daily diabetes management issues alone. Written instructions for recreational activity may avoid this kind of fiasco and the tragic outcome that Johnny could have suffered.

References

  1. Unger J. Diabetes Management in Primary Care, Ch 9. Lifestyle Interventions for Patients with Diabetes, Philadelphia, Pa.: Lippincott Williams & Wilkins,2007 pg 436-454
  2. Beaser RS et al. Joslin’s Diabetes Deskbook, 2nd Ed. Philadelphia, Pa.: Lippincott Williams & Wilkins,2007
  3. Camacho PM, Gharib, H, Sizemore GW. Evidence-Based Endocrinology, 2nd Ed. Philadelphia, Pa.: Lippincott Williams & Wilkins 2007.
  4. Montori VM. Evidence-Based Endocrinology, Totowa, NJ: Humana Press, 2006.
  5. Gerstein HC, Haynes RB. Evidence-Based Diabetes Care, Hamilton, Ont.. BC Decker, 2001.
  6. Unger J. Diabetes Management in Primary Care, Ch 9. Lifestyle Interventions for Patients with Diabetes, Philadelphia, Pa.: Lippincott Williams & Wilkins, 2007 pg 459.
  7. Andreassen CS, Jakobsen J, Andersen H. Muscle Weakness: A Progressive Late Complication in Diabetic Distal Symmetric Polyneuropathy. Diabetes. 2006 55(3): 806-812.
  8. Low PA, Benrud-Larson LM , Sletten DM , et al. Autonomic symptoms and diabetic neuropathy: a population-based study. Diabetes Care, Dec 2004; 27: 2942-7.
  9. Freeman R, Neurogenic Orthostatic Hypotension, N Eng J Med. 358 (6):2008,615-628. Nejm Volume 358:615-624