A 23 year old man is admitted to your intensive care following a near drowning at the local beach. On admission to ICU he has a GCS of 4 and is intubated and ventilated.
a) Briefly list the potential complications from his clinical presentation.
b) What are the risk factors for severe neurological injury?
• Arrhythmia (severe hypothermia)
• Aspiration pneumonitis (water, sand, vomit)
• Acute lung injury/ARDS
• Hypoxic encephalopathy
• Multiple organ dysfunction
• Trauma brain injury or other traumatic injuries (particularly at surf beaches or jetties)
• Electrolyte abnormality
b) Risk factors for severe neurological injury
• At scene
o Immersion > 10 minutes
o Delay in CPR commencement
• In the Emergency Department
o Asystole on arrival in ED
o CPR > 25 minutes
o Fixed dilated pupils and GCS< 5
o Fixed dilated pupils and pH < 7.0
• In the ICU
o No spontaneous movements and abnormal brainstem function at 24 hours
o Abnormal CT scan within 36 hours of submersion
The complications from drowning are best expressed as a structured list.
A) - Aspiration of contaminated water or salt water
B) - Pulmonary oedema, atelectasis, poor gas exchange. High risk of pneumonia.
- Possibly, also ARDS due to surfactant loss (seawater submersion)
C) - Hypotension, circulatory collapse, arrhythmia
D) - Hypoxic brain injury
E) - Transient electrolyte disturbance due to even prolonged submersion. Hypothermia
F) - Hypovolemia due to hydrostatic effects of immersion. Renal failure due to global hypoxia.
It would appear the college generally just wanted the candidates to regurgitate the contents of Box 80.1 (page 820) from the "Submersion" chapter by Cyrus Edibam and Tim Bowles.
Paraphrased, the box contains the following risk factors for death or severe neurological injury:
Factors at the site of submersion:
- Immersion for more than 5 minutes
- Delay in CPR of more than 10 minutes
Factors on presentation to the ED
- Fixed dilated pupils
- GCS of 3
Factors after admission to the ICU:
- GCS less than 6
- Arterial pH less than 7.00 upon arrival to ICU
- No spontaneous purposeful movement and the abnormal brainstem function after 48 hours
- Abnormal CT within 36 hours
The risk factors for poor neurological outcome which appear in the college answer suggest that they consider pre-hospital arrest may have occurred in this patient, in which case all the various cardiac arrest associated risk factors also apply.
The the above box, one may also add the following:
- Warm water drowning
- Submersion time > 10 minutes (a good independent predictor of neurological outcome)
Generally, the risk factors for poor neurological recovery after cardiac arrest can be extracted from the massive table which is featured in the answer to Question 4 from the second paper of 2013, "Describe the clinical signs and investigations available to predict poor neurological outcome in comatose survivors of cardiac arrest."
The ARC ALS2 manual (2011) has a section on drowning (pp. 127). This was my main source of information.
Pearn, John. "The management of near drowning." British medical journal (Clinical research ed.) 291.6507 (1985): 1447.
Giammona, Samuel T., and Jerome H. Modell. "Drowning by total immersion: effects on pulmonary surfactant of distilled water, isotonic saline, and sea water." American Journal of Diseases of Children 114.6 (1967): 612-616.
Modell, Jerome H., et al. "Physiologic effects of near drowning with chlorinated fresh water, distilled water and isotonic saline." Anesthesiology 27.1 (1966): 33-41.
Young, Richard SK, Edwin L. Zalneraitis, and Elizabeth C. Dooling. "Neurological outcome in cold water drowning." Jama 244.11 (1980): 1233-1235.
Suominen, Pertti, et al. "Impact of age, submersion time and water temperature on outcome in near-drowning." Resuscitation 52.3 (2002): 247-254.