Surgery and Healing in the Developing World - Dartmouth-Hitchcock

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106 Surgery and Healing in the Developing World
3. Awaken the patient if you are able to ventilate them adequately by bag/
mask, but are unable to intubate them.
4. Immediately call for surgical assistance if you cannot ventilate the patient.
If the patient desaturates and bradycardia ensues, an emergency
cricothyroidotomy or tracheotomy is indicated.
5. Do not hesitate to implement Pediatric-Advanced Life Support procedures
when indicated.
Laryngospasm
Laryngosoasm is a forceful, involuntary spasm of the laryngeal musculature caused
by stimulation of the superior laryngeal nerve, the sensory innervation of the larynx.
It may occur during an inhalation induction, usually by aspiration of secretions
from the oropharynx. It is most likely to occur as an immediate postextubation
event but may also happen later in the Post Anesthesia Care Unit (PACU) as the
patient wakes up and aspirates blood or oropharyngeal secretions.
Early extubation during the interval between deep anesthesia and fully reacting
is when laryngospasm most commonly occurs.
Laryngospasm must be diagnosed early and treated rapidly. Signs include the
inability to ventilate the patient despite the application of positive pressure by bag/
mask and rapid onset of oxygen desaturation.
Treatment Includes
Institute prolonged positive pressure ventilation and jaw thrust. A small dose of
intravenous succinylcholine (0.25-.05 mg/kg) may be necessary along with controlled
ventilation. Intramuscular succinylcholine (4-6 mg/kg) is effective in patients
without intravenous access and in whom conservative measurers have failed.
Partial laryngospasm occurs more commonly and usually calls for less drastic
measures. It is characterized by inspiratory or expiratory “squeaks” and can usually
be overcome with positive pressure ventilation. Laryngospasm must be rapidly overcome
to avoid postobstructive pulmonary edema. This condition, caused by high
negative intrathoracic pressures generated by spontaneous ventilation against a closed
glottis, is a major cause of morbidity in our patients. It can be diagnosed by the
presence of rales over the lung fields and, in extreme cases, pink frothy fluid (pulmonary
edema fluid) coming from the airway. Additional signs include tachypnea (respiratory
rate greater than 60/min), grunting, retractions, and low oxygen saturation.
If laryngospasm occurs it must be treated immediately and aggressively, with the
institution of controlled ventilation with positive end expiratory pressure (PEEP)
and an intravenous diuretic.
Halothane Overdose
The most common cause of mortality on Operation Smile missions is from too
much halothane during induction. It is a problem that can be avoided if one remains
aware during induction of where the halothane vaporizer is set in relation to
the patient’s vital signs. This awareness, part of the vigilance required to practice safe
anesthesia, is too often lost in the crush of too many cases, too little sleep, jet lag
and/or a difficult airway. To solve this problem we have introduced the Halothane
Countdown, detailed in “Preoperative” section.
The signs of halothane overdose include loss of pulse oximetry, muffled or absent
heart tones, severe hypotension, a pale or dusky patient, and cardiac
dysrhythmias.