Diagnostic Considerations

A common error in the management of hypovolemic shock is failure to recognize it early, often caused by a reliance on BP or initial hematocrit level, rather than signs of decreased peripheral perfusion, to make the diagnosis. This error leads to delay in diagnosing the cause and in resuscitating the patient.

Also note the following:

• Injuries in patients with trauma can be missed, especially if the examiner focuses on more obvious injuries. This error can be avoided by completing a full physical examination, continuously and closely monitoring the patient's status, and performing serial examinations.

• Elderly individuals have less tolerance for hypovolemia compared with the rest of the general population. Aggressive therapy should be instituted early to prevent potential complications, such as myocardial infarction and stroke.

• In patients who require extensive volume resuscitation, care should be taken to prevent hypothermia, because this can contribute to arrhythmia or coagulopathy. Hypothermia can be prevented by warming the intravenous fluids prior to their administration.

• Patients taking beta-blockers or calcium-channel blockers and those with pacemakers may not have a tachycardia response to hypovolemia; this lack of response may lead to a delay in the diagnosis of shock. To minimize this potential delay, history taking should always include questioning about medications. The examiner should also rely on signs of decreased peripheral perfusion other than tachycardia.

• Coagulopathies can occur in patients receiving large amounts of volume resuscitation. This is due to dilution of platelets and clotting factors but is rare within the first hour of resuscitation. Baseline coagulation studies should be drawn and should guide the administration of platelets and fresh frozen plasma.

In addition to physical symptoms, the various testing methods to confirm hypovolemic shock include:

• Blood testing to check for electrolyte imbalances, kidney, and liver function

• CT scan or ultrasound to visualize body organs

• Echocardiogram, an ultrasound of the heart

• Electrocardiogram to assess heart rhythm

• Endoscopy to examine the oesophagus and other gastrointestinal organs

• Right heart catheterization to check how effectively the heart is pumping

• Urinary catheter to measure the amount of urine in the bladder