Delayed onset and long-lasting hemidiaphragmatic paralysis and cranial nerve deficit after interscalene nerve block for rotator cuff repair in beach chair position.

Hemidiaphragmatic paralysis is the most common adverse effect associated with interscalene block. In most cases, it resolves with the resolution of nerve blockade with only an estimated incidence of 0.048% persisting for longer duration. Occasionally, interscalene block is also associated with recurrent laryngeal nerve block and seldom with cranial nerve paresis. We present a case of delayed onset and prolonged hemidiaphragmatic paralysis that was associated with 3 cranial nerve deficits after interscalene nerve block for shoulder surgery performed under general anesthesia in the beach chair position. Etiology is unclear, but most likely multifactorial.

Activated cranial cervical cord neurons affect left ventricular infarct size and the potential for sudden cardiac death.

To evaluate whether cervical spinal neurons can influence cardiac indices and myocyte viability in the acutely ischemic heart, the hearts of anesthetized rabbits subjected to 30 min of LAD coronary arterial occlusion (CAO) were studied 3h after reperfusion. Control animals were compared to those exposed to pre-emptive high cervical cord stimulation (SCS; the dorsal aspect of the C1-C2 spinal cord was stimulated electrically at 50 Hz; 0.2 ms; 90% of motor threshold, starting 15 min prior to and continuing throughout CAO). Four groups of animals were so tested: 1) neuroaxis intact; 2) prior cervical vagotomy; 3) prior transection of the dorsal spinal columns at C6; and 4) following pharmacological treatment [muscarinic (atropine) or adrenergic (atenolol, prazosin or yohimbine) receptor blockade]. Infarct size (IS) was measured by tetrazolium, expressed as percentage of risk zone. C1-C2 SCS reduced acute ischemia induced IS by 43%, without changing the incidence of sudden cardiac death (SCD). While SCS-induced reduction in IS was unaffected by vagotomy, it was no longer evident following transection of C6 dorsal columns or atropinization. Beta-adrenoceptor blockade eliminated ischemia induced SCD, while alpha-receptor blockade doubled its incidence. During SCS, myocardial ischemia induced SCD was eliminated following vagotomy while remaining unaffected by atropinization. These data indicate that, in contrast to thoracic spinal neurons, i) cranial cervical spinal neurons affect both adrenergic and cholinergic motor outflows to the heart such that ii) their activation modifies ventricular infarct size and lethal arrhythmogenesis.

[Effect of transection or pretreatment of the infraorbital nerve with snake venom on the analgesia induced by electroacupuncture of "Sibai" (ST 2) acupoint in visceral pain rats].

OBJECTIVE: To observe the role of large-diameter fibers of infraorbital nerve (ION) in "Sibai" (ST 2)-electroacupuncture (EA) induced analgesia in visceral pain (VP) rats. METHODS: A total of 36 SD rats were randomized into control, VP, EA, ION transaction, snake venom (SV) and saline groups, with 6 rats in each group. EA(2 Hz/20 Hz) was applied to bilateral "Sibai" (ST 2) for 20 min. VP model was established by intraperitoneal injection of 0.6% acetic acid (10 mL/kg). Bilateral ION were transacted or pretreated by regional application of snake venom to selectively destroy A fibers,respectively. Behavior reactions were assessed by counting abdominal muscular contractions. Meanwhile, c-fos expression in the nucleus of the solitary tract (NTS) and paratrigeminal nucleus (PTN) was displayed by immunohistochemistry. RESULTS: In comparison with control group, the numbers of abdominal muscular contraction,and c-fos immuno-reaction (IR) positive neurons in both NTS and PTN increased significantly in VP group (P < 0.001); while in comparison with VP group, the numbers of the abdominal contraction, and c-fos IR-positive neurons of both NTS and PTN in EA and SV and saline groups decreased considerably (P < 0.05, P < 0.01). No significant differences were found between ION transaction and VP groups in the abdominal contraction number, and c-fos IR-positive neurons in both NTS and PTN areas,and among EA and SV and saline groups in the numbers of abdominal contraction and c-fos IR-positive neurons of both NTS and PTN (P > 0.05). CONCLUSION: The large-diameter (A) fibers of ION are not the major afferent fibers affecting EA-ST 2 induced analgesia in visceral pain rats; and somatic sensory afferents from orofacial areas and visceral pain input converge in the NTS and PTN, which may be the basis of the EA analgesia in the present study.

Greater occipital nerve block using local anaesthetics alone or with triamcinolone for transformed migraine: a randomised comparative study.

OBJECTIVE: To determine whether adding triamcinolone to local anaesthetics increased the efficacy of greater occipital nerve block (GONB) and trigger-point injections (TPIs) for transformed migraine (TM). METHODS: Patients with TM were randomised to receive GONB and TPIs using lidocaine 2% and bupivacaine 0.5% + either saline or triamcinolone 40 mg. We assessed the severity of headache and associated symptoms before and 20 minutes after injection. Patients documented headache and severity of associated symptoms for 4 weeks after injections. Changes in symptom severity were compared between the two groups. RESULTS: Thirty-seven patients were included. Twenty minutes after injection, mean headache severity decreased by 3.2 points in group A (p<0.01) and by 3.1 points in group B (p<0.01). Mean neck pain severity decreased by 1.5 points in group A (p<0.01) and by 1.7 points in group B (p<0.01). Mean duration of being headache-free was 2.7+/-3.8 days in group A and 1.0+/-1.1 days in group B (p = 0.67). None of the outcome measures differed significantly between the two groups. Both treatments were well tolerated. CONCLUSIONS: Adding triamcinolone to local anaesthetics when performing GONB and TPIs was not associated with improved outcome in this sample of patients with TM.

[Techniques of local anesthesia in the area of the head]. / Techniken der Lokalanästhesie im Gesichtsbereich.

In the head and neck region, many procedures can be performed under local anesthesia. The anesthetic agent can be applied onto the surface of the skin or mucosa (surface anesthesia), it can be infiltrated into the tissue to be treated, or it can be used to block the regional sensory nerve (conduction anesthesia). In this paper, the most important techniques for local anesthesia of the face are presented as a short clinical guide.

Maternal vitamin A supplementation in relation to selected birth defects.

High doses of vitamin A cause birth defects in animals. Concern over vitamin A teratogenicity in humans has been prompted by reports of teratogenic effects of the vitamin A analogue, isotretinoin. The pattern of defects observed among isotretinoin- and vitamin A-exposed infants and animals suggests a possible mechanism involving cranial neural crest cell activity. Data from a case-control study were used to assess maternal use of vitamin A supplements alone and vitamin A-containing multivitamin supplements in relation to the occurrence of certain birth defects involving structures derived, at least in part, from cranial neural crest cells. Cases were 2,658 infants with such defects (primarily craniofacial and cardiac malformations). Controls were 2,609 infants with other malformations. Vitamin A supplementation was defined as daily use for at least 7 days of retinol alone or with vitamin D, or of fish oils. Information on vitamin A dose and nutrition was not available. The mothers of six controls used vitamin A supplements in each of the first three lunar months of pregnancy in comparison to the mothers of 15, 14, and 10 cases in lunar months 1, 2, and 3, respectively. Relative risk estimates and 95% confidence intervals were 2.5(1.0-6.2) for lunar month 1, 2.3(0.9-5.8) for lunar month 2, and 1.6(0.6-4.5) for lunar month 3. These findings should be considered tentative because no dose information was available, small numbers of cases and controls were exposed to vitamin A supplements, and relative risk estimates were not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Transient diplopia from a posterior alveolar injection.

Several anatomical vascular pathways have been proposed to explain oculomotor disturbances observed after injection of local dental anesthetics. The author suggests another possible pathway to account for the unusual clinical observations described in this report.