In dentistry practice occurance of lethal complications connected with anesthesia are very rare. Forensic medicine expertise in two cases of such complications are presented in our report.
A 6-year-old girl. Diagnosed periodontitis of 25th milk-tooth, indicated extraction of this tooth. For the local buccal and mandibular anesthesia injected 2 ml of 2% Lignocaine hydrochloride. After 2-3 minutes appeared sight disorders, vomiting, cramps, unconsciousness. After some more minutes - apnoe. Invited reanimatologist achieved renewal of unstable breathing. With a help of artificial lung aeration life is supported up to 16 hours. As functions of the brain cortex did not appear, after 16 hours entered death. During the reanimation process patient received epinephrine, atropine, prednisolone, after that dexamethasone, theophyline, furosemid, analgin, corglycone, ampicillin, gentamicin.
Autopsy findings: marked brain and lungs oedema, intensive congestion of viscera, multiple small hemorrhages on heart's and lung's surfaces, dissiminated athelectases in lungs.
Histopathological findings: in lungs - changes characteristic for artificial breathing, microthrombi in brain capillaries.
Forensic toxicological examination was not performed.
A 30-year-old male was ill with bronchial asthma, congenital stenoses of aortical apertura and coarctation of aorta. For the sanation of mouth cavity indicated extraction of four teeth roots. Conclusion of anesthesist - risk of narcosis of I-II degree. In intravenal narcosis of 0,1% Atropine hyhrochoride 1,0, Tramadol 0,1 g, Ketamine 0,1 g length 15 minutes, extracted four teeth roots. In awakening phase sudden colapss, Biot breathing. Reanimation in the dentist room longed for 20 minutes. Patient received epinephrine, atropine, prednisolone. Continuation of reanimation - in the intensive therapy ward - for 30 minutes, where, intended, the patient has been conveyed already after the death of brain.
Autopsy showed fast entered death symptoms: pulmonary, liver, pancreas, kidney and encephalic congestion, as well, mentioned, congenital heart pathology. Autopsy was performed by pathologist.
Toxicological analysis was not done.
In case 1 was discussed question of the essence of anesthesia complications - anaphylactic shock or side effect of anesthetic in kind of hypersensitive reaction. In anamnesis found negative aspects- born with Caesarean section, asthmatical bronchitis, functional cardiopathia, asthenisation of CNS. 11
Lignocaine - versatile local anesthetic is administered topically and by injection for producing prompt local anesthetic effects in a variety of clinical situations. 1 to 2-percent solution is usually employed by injection in dental practice. Two types of toxic reaction can occur when plasma level of Lignocaine rises abruptly as a result of overdosage or accidental intravenous injection of this drug into the systemic circulation. These are central (1) nervous system stimulation and depression and (2) cardiovascular depression. Central nervous system reactions can express oneself in variety forms. The patients became nervous, confused and disoriented, they may begin to tremble and then develop convulsive spasms. Convulsions may be quickly followed by loss of reflexes, coma, and respiratory depression and failure.
The possible cardiovascular reactions may be as hypotensive reaction or cardiac reaction. Blood pressure falls gradually or abruptly. Patient shows pallor and may complain of feeling faint and dizzy. Patient may become drowsy and pass into comatose state as blood pressure falls to shock levels. Cardiac reaction - heart rate may slow down markedly, pulse pressure is reduced. Cardiac standstill or ventricular fibrilation may develop suddenly.
Cause of death by experts commision was ruled as toxic reaction to Lignocaine, at greatest credibility, on accounnt of accidental drug intravascular getting in.
As negative factors promoting entrance of death were considered asthmatical bronchitis, functional cardiopathia, asthenisation of CNS.
In second case - extraction of teeth roots under general anesthesia by intravenous Ketamine and Tramadol injection with premedication with Atropine.
Ketamine (Calypsol, Ketalar) as an injectable nonbarbiturate anesthetic produces a state in which the patient does not seem to be asleep but remains immobile and unresponsive to painful stimuli. This unique state of deep analgesia without actual sleep or awareness has been called cataleptic or dissociative anesthesia.
This drug can be used in certain diagnostic procedures (bronchoscopy, pneimoencephalography) and for brief painful procedures such as burn debridement and also dental extractions.
It is possible arrainsing any adverse effects by application of Ketamine. The heart rate and blood pressure often rise during the first few minutes. Patients with cardiac pathology should be continously monitored. The drug is not recommended for patients with moderately severe hypertension or coronary disease.
Ketamine is given by intravenously rout in doses ranging from 1 mg to 4,5 mg/kg.
One of the drawbacks of this anesthetic is that some patients become confused and excited or have hallucinations when coming out of anesthesia. Therefore the monitoring during the recovery period must be careful.
In regard to Tramadol (Tramal) - it is a comparatively new analgesic agent with a dual mechanism of action that includes weak agonistic effects at the Mu-opioid receptor as well as inhibition of neurotransmitter (serotonine, norepinephrine) re-uptake.
Although Tramadol has proven to be a safe and effective agent for the control of pain, adverse effects can occur with its use (drowsiness, vertigo, nausea, headache). These adverse effects are not life-threatening, more severe effects can be anticipated from a true overdose of the medication.
Appropriate dosing for Tramadol is 0,5 mg/kg 1 mg/kg every 3 to 4 hours.
Experts conclusion - former diseases, which significance for general anesthesia was underestimated were determinant by occurrence of lethal complications.
In process of judical investigation arose the question about eventual role of latex alergy in the origin of narcosis complications. (The dentist had applied latex gloves). But any true medical affirmations for this version were not established by forensic medicine expertise.
Presented practical cases obviously show - as well in dentistry practice the questions of local and general anesthesia are to solve with greatest thoughtfulness bearing in mind former endured illnesses and present common state of health.