Hypothermia: a case presentation and review of the pathophysiology and options for prevention and treatment

MS Logan, MD; CM Watson MD, JE Morrison MDUniversity of South Carolina, School of Medicine, Columbia, South Carolina

Classification Traditional Trauma

Mild 35-32 °C 35-34 °C

Moderate 32-28 °C 34-32 °C

Severe <28 °C <32 °C

Type Method Rate

Basal Heat Production 1.2°C per hour

Passive External Warm EnvironmentBlanketsShivering

0.5 – 2°C per hour

3.6°C per hour

Active External Immersion in warm waterElectric blankets Environmental heatersConvective air blankets

1.4 – 2.4°C per hour

Active Core Warm gastric lavageWarm pleural lavageColonic lavageThoracic lavageInhalational gasesIntravenous fluidsExtracorporeal circulation

1 – 4°C per hour

Active Core Extracorporeal Methods

HemodialysisCardiopulmonary bypassContinuous arteriovenous

rewarming

1 – 3°C every 5 min

Tsuei BJ, Kearney PA. Hypothermia in the trauma patient. Injury Int J Care Injured. 2004:35;7-15

Body System Degree of Hypothermia

Mild (34-36 °C) Moderate (32-34°C) Severe (<32°C)

General/Metabolic Shivering Increased oxygen consumption Acidosis

Increased oxygen consumption Increasing anaerobic metabolism

Cardiovascular Vasoconstriction Bradycardia Ventricular arrhythmias/Asystole

Tachycardia Depressed/Irritable myocytes

Decreased cardiac output

Atrial arrhythmias

Respiratory Tachypnea Depressed respiratory drive Apnea

Bronchospasm Decreased gag reflex

Neurologic Confusion Decreased level of consciousness Coma

Hyperreflexia Hyporeflexia/Absent reflexes

Renal Cold diuresis Oliguria

Gastrointestinal Decreased motility Gastric ulcers

Hemorrhagic pancreatitis

Coagulation Prolonged PT, aPTT, platelet dysfunction Progressive coagulopathy

Kirkpatrick AW, Chun R, Brown R, Simons RK. Hypothermia and the trauma patient. Can J Surg. 1999 Oct;42(5):333-43.

Tsuei BJ, Kearney PA. Hypothermia in the trauma patient. Injury Int J Care Injured. 2004:35;7-15

Classification of Hypothermia

A 20-year-old female presented to our level 1 trauma center after being found on a roadside embankment. It appeared that she had been ejected from her vehicle after a motor vehicle collision the previous night.

On arrival she was noted to be in ventricular fibrillation. She had a core body temperature of 27.5°C by bladder probe, blood pressure of 81/59, initial arterial blood gas results of pH 7.03, pCO2 55 mmHg, paO2 86 mmHg and base deficit of -17 mmol/L on 100% nonrebreather.

Advanced Trauma Life Support guidelines were followed. Her initial resuscitation lasted for approximately three hours to include intubation, central venous access, bilateral chest tube thoracostomy with warm saline lavage, diagnostic peritoneal lavage with warm saline lavage, bladder lavage, orogastric lavage, multiple arterial blood gases and multiple rounds of cardiopulmonary resuscitation with cardioversion.

She had multiple thoracic, intraabdominal, orthopedic and spinal injuries. Of significance, complete spinal cord transection was recognized on abdominal computed tomography (CT) scan (Figure 1). She required several operative procedures (Figure 2). Her intensive care unit stay included most major complications associated with hypothermia, specifically, coagulopathy, acidosis, cold bronchorrhea, cold diuresis, ileus, cardiovascular conduction abnormalities, and central nervous system depression.

After recovery she was transferred to a long term rehabilitation center.

•Common

•12% pts arrive with hypothermia12% pts arrive with hypothermia

•46% hypothermic on arrival to operating room (OR)46% hypothermic on arrival to operating room (OR)

•76% leaving OR are hypothermic76% leaving OR are hypothermic 3

•Morbidity and Mortality:

•Critical Point: < 34°C enzymatic dysfunction4

•Core temp < 32Core temp < 32°C

•Exposure alone - 23% mortality Exposure alone - 23% mortality

•Trauma + hypothermia - 100% mortalityTrauma + hypothermia - 100% mortality55

•No threshold temperature below which mortality is assuredNo threshold temperature below which mortality is assured66

•Reported survival with core temperature below 17Reported survival with core temperature below 17°C7

Case

Discussion

RewarmingThe Body’s Response

Fig 2: Intraoperative PhotographFig 1: CT Reconstruction of the Spine

3Gregory JD, Flancbaum L, Townsend MC, Cloutier CT, Jonasson O. Incidence and timing of hypothermia in trauma patients undergoing operations. J Trauma 1991 Jun:31(6):795-8.4 Watts DD, Trask A, Soeken K, Perdue P, Dols S, Kaufmann C. Hypothermic coagulopathy in trauma: effect of varying levels of hypothermia on enzyme speed, platelet function and fibrinolytic activity. J Trauma. 1998 May; 44(5): 846-54.5Jurkovich GJ, Greiser WB, Luterman A, Curreri PW. Hypothermia in trauma victims: an ominous predictor of survival. J Trauma. 1987;27:1019-24.6Rutherford EJ, Fusco MA, Nunn CR, et al. Hypothermia in critically ill trauma patients. Injury. 1998;29(8):605-8.7Gilbert M, Busund R, Skagseth A, Nilsen PA, Solbo JP. Resuscitation from accidental hypothermia of 13.7 degrees C with circulatory arrest. Lancet. 2000:355:375-6.

Hildebrand Frank, Giannoudis Peter V, van Griensven Martijn, Chawda Mayur, Pape Hans-Christoph. Pathophysiologic changes and effects of hypothermia on ourcome in elective surgery and trauma patients. Am J Surg 2004;187(3):363-71.