All posts by TheTraumaPro

Trauma 20 Years Ago: CAVR For Hypothermia

Hypothermia is the bane of major trauma resuscitation, causing mortality to skyrocket. A number of rewarming techniques have been developed over the years. These are classified as passive (the patient generates their own heat) or active (we deliver calories to them), and noninvasive vs invasive. Rewarming speed increases as we move from passive to active and from noninvasive to invasive.

Continuous arteriovenous rewarming (CAVR) is one of the invasive techniques used today. Its use in humans was first reported 20 years ago this month. Larry Gentilello at Harborview in Seattle had experimented with this technique in animals, and reported one case of use in a human who had crashed his car into icy water. After a 20 minute extrication, the patient was pulseless with fixed and dilated pupils, but he regained pulse and blood pressure at the hospital.

The initial core temperature was 31.5C. Peritoneal, bladder and gastric lavage were carried out for warming, as was delivery of warm inspired gas via the ventilator. However, after an hour the temperature had dropped to 29.5C. CAVR was initiated as a last-ditch effort using a jerry-rigged Rapid Fluid Warmer from Level 1 Technologies. The core temperature was raised to 35C after 85 minutes.

The patient did have typical complications (ARDS, acute renal failure), but survived with recovery of his renal and pulmonary function, and a normal neurologic exam. At the time, the authors were unsure whether the complications were due to the near-drowning or the rapid rewarming.

Reference: Continuous arteriovenous rewarming: report of a new technique fo9r treating hypothermia. J Trauma 31(8):1151-1154, 1991.

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Procedural Sedation and Analgesia

The Regions Hospital Multidisciplinary Trauma Conference on August 4 dealt with the use of procedural sedation in the emergency department. The presentation was delivered by Ben Watters MD.

This presentation is 56 minutes long. 

Important disclosure information: off-label use of ketamine is discussed.

Obit: Max Harry Weil MD – Feb 9, 1927-July 29, 2011

Some people may recognize the name, but few can comprehend how much this man has done for the fields of trauma and critical care. Dr. Weil was a world-class clinician, teacher and researcher, and is believed to have coined the phrase “critical care medicine.”

Some of his many notable accomplishments:

  • In 1955, Dr. Weil created the first bedside shock cart, which is now known as the crash cart. 
  • In the late 1950’s, he and his colleagues recognized that some patients who were seriously ill or who had undergone major surgery had a propensity to die at night. He hit upon the concept that having an area for closer monitoring of these patients might allow for earlier recognition of acute problems and earlier intervention to correct them. This led to the creation of a four bed “shock ward.” This was the precursor to the first intensive care unit, which opened in 1968.
  • Introduced automated vital signs monitors in 1961.
  • Created the first computer assisted diagnosis tools in 1976.
  • Developed the STAT lab concept for rapid results in critically ill patients in 1981.

He was the co-inventor for 22 patented devices including:

  • Resuscitation blanket to protect medical personnel from electric shocks when defibrillating patients (2002).
  • Capnometer for assessing the severity of shock which can be placed in the upper GI tract or under the tongue (2001).
  • The Weil Mini Chest Compressor (2006)
  • An IV pump system (1981), detection for occlusion or infiltration (1985)
  • Osmotic pressure sensor (1977)
  • High frequency ventilator (1983)
  • A method for identifying cardiac rhythm even while CPR is in progress (2006)

Dr. Weil established the Institute for Critical Care Medicine in 1961, and worked there full-time after he left the University of Southern California. The institute trains physicians and engineers to discover and develop concepts and methods for more beneficial life-saving medical management. He stepped down as the president of the institute in 2006, but continued to work there full-time until two weeks before he died. 

The world has lost a true physician, teacher and innovator.

Link: Weil Institute for Critical Care Medicine

Algorithm For Nonoperative Management of Blunt Hepatic Trauma

Yesterday, I posted the Western Trauma Association’s algorithm for operative management of blunt liver trauma. Click here to view it. Today, I’m going to discuss their algorithm for nonoperative management. 

The algorithm is fairly self-explanatory. Click on the image above to read the annotated text for details on each step. Note: this requires full access to the Journal of Trauma.

Some key points in this algorithm:

  • Unstable patients need rapid identification of the cause. If the FAST is positive ©, then you need to go to the OR and use the operative algorithm.
  • CT scan is used for diagnosis in stable patients (F), but if a liver injury is seen and they become unstable at any time, go to the OR.
  • Contrast extravasation in a stable patient should prompt an evaluation and possible embolization by interventional radiography (G).
  • If complications develop (SIRS, abdominal pain, fever, jaundice), a repeat CT is indicated (K).
  • Abscesses and focal collections of bile may be managed by interventional radiology (L,M). Persistent bile leak may be decreased by ERCP and sphincterotomy (O).
  • Bile ascites or large hemoperitoneum may be managed using laparoscopy with drainage (N).

Reference: Western Trauma Association critical decisions in trauma: nonoperative management of adult blunt hepatic trauma. J Trauma. 67:1144–1148, 2009.

Algorithm For Operative Management of Blunt Hepatic Trauma

The Western Trauma Association has just published guidelines on decision-making when faced with hepatic injury in the OR. The algorithm is based on the available literature, which contains little prospective, randomized trial data. Nonetheless, it is a valuable tool that can be used to develop your own institution-specific protocol.

The algorithm is fairly self-explanatory. Click on the image above to read the annotated text for details on each step. Note: this requires full access to the Journal of Trauma.

Some key points in this algorithm:

  • Simple hemostatic maneuvers are usually successful with minor bleeding (A).
  • Sequential use of more involved maneuvers is indicated for major bleeding. In order, they are packing (B), Pringle maneuver (D), selective vessel ligation within the liver (E), and finally selective hepatic artery ligation (F).
  • Damage control laparotomy and interventional radiology are useful adjuncts.

Tomorrow I’ll write about the nonoperative blunt hepatic trauma algorithm. Click here to view it.

Reference: Western Trauma Association/Critical Decisions in Trauma: operative management of adult blunt hepatic trauma. J Trauma 71(1):1-5, 2011.