Monitoring Critically Ill Patients

Vital basics on vital signs and other signs that are vital.

Our goal in medicine is to gather and organize data, interpret that data and ultimately make decisions in the prevention, diagnosis, and management of disease.  The initial part of this system is to ensure that adequate and correct data is collected and interpreted with knowledge of the process and shortcomings that the data was collected with.

Discussion includes vital signs, pulse oximetry, blood gases, capnography/end-tidal C02 (ETC02) and more.  It is important to recognize where vital signs can trick you, how to deal with pulse oximetry latency and how blood gases and ETC02 can be interpreted in the setting of shock.

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Monitoring Critically Ill Patients PDF


Meyers CM, Weingart SD. Critical Care Monitoring In The Emergency Department. Emergency Medicine Practice. 2007;(9)7:1-23.

Assali AR, Herz I, Vaturi M, Adler Y, Solodky A, Birnbaum Y, Sclarovsky S. Electrocardiographie criteria for predicting the culprit artery in inferior wall acute myocardial infarction. Am. J. Cardiol. 84(1); 87-9

Ding ZN, Shibata K, Yamamoto K, Kobayashi T, Murakami S. Decreased circulation time in the upper limb reduces the lag time of the finger pulse oximeter response. Can J Anaesth. 1992 Jan;39(1):87-9.

Goldberg AL. Electrocardiogram in the diagnosis of myocardial ischemia and infarction. In: UpToDate, Ganz, LI (Ed , UpToDate, Waltham, MA, 2013.

Goldberger AL, Stein PK. Evaluation of heart rate variability. In: UpToDate, Ganz, LI (Ed), UpToDate, Waltham, MA, 2013.

Elert, Glenn (2005). “Temperature of a Healthy Human (Body Temperature)”. The Physics Factbook. Retrieved 2007-08-22.

Ellender TJ, Skinner JC. The use of vasopressors and inotropes in the emergency medical treatment of shock. Emerg Med Clin N Am. 26 (2008) 759-786

Jin x, Weil MH, Tang W, Povoas H, Pernat A, Xie J, Bisera J. End-tidal carbon dioxide as a noninvasive indicator of cardiac index during circulatory shock. Crit Care Med. 2000 Jul;28(7):2415-9.

Kelly G (December 2006). “Body temperature variability (Part 1): a review of the history of body temperature and its variability due to site selection, biological rhythms, fitness, and aging”. Altern Med Rev 11 (4): 278–93. PMID 17176167.

Levin T, Goldstein JA. Right ventricular myocardial infarction. UpToDate

Mackay MH, Ratner PA, Johnson JL, Humphries KH, Buller CE. Gender differences in symptoms of myocardial ischaemia. Eur Heart J 2011;32:3107-3114.

Mackowiak, P. A.; S. S. Wasserman, M. M. Levine (1992-09-23). “A critical appraisal of 98.6 degrees F, the upper limit of the normal body temperature, and other legacies of Carl Reinhold August Wunderlich”. JAMA 268 (12): 1578–1580. doi:10.1001/jama.268.12.1578. PMID 1302471. Retrieved 2007-08-22.

Marino, Paul. The ICU Book, 3rd Edition. Ovid Technologies, Inc. 2006

Mateer, J.R., et al. Continuous pulse oximetry during emergency endotracheal intubation. Ann Emerg Med 1993;22(4):675-9.

Meyers CM, Weingart SD. Critical Care Monitoring In The Emergency Department. Emergency Medicine Practice. 2007;(9)7:1-23.

Reeder GS, Kennedy HL, Rosenson RS. Overview of the acute management of ST elevation myocardial infarction. UpToDate

Ryan TJ, Reeder GS. Initial evaluation and management of suspected acute coronary syndrome in the emergency department. UpToDate

Prause G, Hetz H, Lauda P, Pojer H, Smolle-Juettner F, Smolle J. A comparison of the end-tidal-CO2 documented by capnometry and the arterial pCO2 in emergency patients. Resuscitation. 1997 Oct;35(2):145-8

Polielinicio SD. Use of inhaled nitric oxide in the treatment of right ventricular myocardial infarction. Am. J. or Emerg. Med. 29;473.e3-473.e5

Spalding MB, Ala-Kokko TI, Kiviluoma K, et al. Inhaled nitric oxide effectively decreases right heart afterload following right heart infarct in pigs. Scand Cardiovasc J 2001;35(1):45-9

Weingart S. Physiology of oxygenation. Emcrit audio podcast

3 Comments on “Monitoring Critically Ill Patients”

  1. brian robinson says:

    Is there more information for that picture?

    • Brandon Parker says:

      yea, sorry I will discuss this concept in the podcast and in the notes. Essentially what it is showing is that ETC02 is a depiction of ventialation more than perfusion in pts with normal CO but with declining CO those parameters swap and after a drop of 40% the ETC02 is a measurment of CO.

  2. Carl Yu says:

    thanks! Learned a lot

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