A free radical is any chemical capable of independent existence containing one or more unpaired electrons. The unpaired electron alters the chemical reactivity of the molecule/atom, making it more reactive than the corresponding non-radical form. When a free radical is formed, it tries to complete its valance by bonding to another atom, which may create another free radical and another, and another. The chain reaction that occurs may eventually result in cellular death.
Read the following case study and answer the questions at the end.
A 58 year old man experiences sudden cardiac arrest at home while watching football with his family. The patients son witnesses his father collapse, calls 911 and reports the incident. The dispatcher coaches the son in hands only chest compressions on his father. The police arrive within two minutes and applies an AED to the father which advises to defibrillate. One shock is delivered and the police officer takes over compressions and the son provides ventilations. One minute later the fire department arrives and takes over cardiopulmonary resuscitation from the police officer and son. A second shock is advised by the AED and the patient is again defibrillated. The BLS crew administers oxygen at 15 LPM to the BVM while assisting ventilations and performing compressions.
Paramedics arrive from the local ambulance service and initiate intravenous access and endotracheal intubation while the fire crew continues high performance CPR. At the end of this two minute cycle of CPR the patients rhythm is analyzed and determined to be ventricular fibrillation. A third shock is delivered. CPR begins again and the paramedics administer 1 mg of epinephrine. On the next rhythm check, after two minutes of CPR, the rhythm is determined to be a sinus tachycardia with a pulse. The patient remains unconscious and the EMS personnel prepare the patient for transport.
In route the patient is assessed and found to have a strong pulse at 115 beats per minute but remains apneic. His ventilations are assisted via the ET tube at 12 per minute with a BVM attached to 100% oxygen at 15 LPM flow. His blood pressure is 86/52 with a GCS of 3. The patient has no significant medical history other than mild hypertension for which he takes Lisinopril. They arrive at the hospital in five minutes, approximately 10 minutes after the patient collapsed.
What factors presented to this point in the scenario that indicate this patient has an improved chance of survival from his sudden cardiac arrest?
On arrival to the Emergency Department, report is given to the medical and nursing staff. The patient remains unresponsive, with a strong pulse, continues to be apneic with assisted ventilations and a low blood pressure. The IV is infusing a crystalloid solution and the ET tube is positioned correctly. Arrangements are made to transfer the patient to the cardiac catheterization lab for an emergent angiography and intervention. The ED begins targeted temperature management of a core body temperature between 32 and 36 degrees Celsius for 24 hours and restrict oxygen administration to maintain oxygen saturations between 94 and 99% in preparation for transfer to the cardiac catheterization lab.
What are the advantages and disadvantages to targeted temperature management in the post cardiac arrest victim?
What are the advantages and disadvantages of titrated oxygen administration?Tags: define, pathophysiology