Kanemitsu Higashi

Fundamental patterns and characteristics of the laser-doppler skin blood flow waves recorded from the finger or toe

Three different components, Basic Wave (BW), Cardiac Wave (CW) and Reflex Wave (RW), among the laser-Doppler (L-D) skin blood flow waves on the finger- or toe-tip, were studied in 32 healthy volunteers. The cycle of the rhythmic BW was 8.1 +/- 1.7.min-1 and was independent of respiratory movements. The BW was synchronous with the baseline fluctuation in the digit-photoplethysmogram. Power spectral analysis of rhythmic fluctuations in the simultaneously recorded R-R interval on ECG, systolic blood pressure, and L-D skin blood flow disclosed that the BW was correspondent with the Mayer wave, i.e., low frequency component. The cycle of the CW was consistent with the heart rate and was superimposed on the BW. The RW was a transient marked reduction in blood flow, which was induced by a deep inspiration or various sensory stimuli. A sympathetic skin response on the palm and a venoconstrictive response on the occluded arm were observed concomitantly with the RW. Good synchronization was observed in each component of the L-D skin flow waves between the fingers and toes. These findings suggest that the BW and the RW on the finger- or toe-tip are predominantly driven by tonic and reflex phasic activities of descending sympathetic outflows via the supraspinal center, respectively.

Effects of neural blockade and general anesthesia on the laser-Doppler skin blood flow waves recorded from the finger or toe

Effects of neural blockade and general anesthesia on the basic wave (BW) and the reflex wave (RW) among the laser-Doppler (L-D) skin blood flow waves recorded on the finger or toe were studied in 2 volunteers and 42 patients. The BW was continuous, rhythmic and independent of respiratory movements. The RW, which was induced by a deep inspiration or a snapping sound, was a transient marked reduction in blood flow. The BW was almost flattened and the RW was no longer induced at the finger under complete wrist block (n = 2), or under cervical or upper thoracic epidural anesthesia extended caudally over T7 (n = 2). On the other hand, the BW was still detected with reducing frequency and the RW could be provoked with one exception at the finger on the side with a sympathetic ganglion block at the C6 vertebral level (n = 14). The BW and RW at the toe were retained under lumbar subdural anesthesia (n = 6) as well. However, under the combination of lumbar subdural anesthesia and lower thoracic epidural anesthesia extending rostrally over T4 (n = 6), both the BW and the RW disappeared at the toe. In the course of deepening nitrous oxide/enflurane anesthesia (n = 10), the BW gradually reduced in frequency until it was almost flattened, and it became difficult to provoke the RW. L-D flowmetry of the finger or toe could be a useful clinical measure for detecting the presence or absence of sympathetic function controlling cutaneous vasomotion.

Effects of systemic cooling and rewarming on the evoked spinal cord potentials and local spinal cord blood flow in dogs.

Changes in evoked spinal cord potential (ESCP) and in local spinal cord blood flow (local SCBF) were measured simultaneously in eight dogs in the course of systemic cooling and rewarming using a water mattress. PaCO2 was maintained at 35-40 mm Hg (temperature-uncorrected values) by adjusting ventilatory volume every 1 degree C change of esophageal temperature under N2O (60%)-O2-isoflurane (1.15%) anesthesia. Local SCBF and arterial blood pressure decreased and ESCP latencies increased linearly with the decrease in body temperature to 23-24 degrees C. The conductive ESCPs (non-synaptic components) showed temporary augmentation in amplitude before eventual decrease under cooling. These showed a tendency to return to the precooling baselines after the initiation of rewarming. These results demonstrate that conductive ESCPs could be available for intraoperative monitoring of spinal function under hypothermia down to 23-24 degrees C.

Non-neurogenic periodic fluctuations in heart rate and vasomotion appearing in familial amyloid polyneuropathy (FAP) Type I (Met30)

In order to evaluate the function of the autonomic nervous system, power spectral analysis of heart rate fluctuation and waveform observation of cutaneous vasomotion were conducted in 3 patients with familial amyloid polyneuropathy Type 1 (FAP) (Met30) with autonomic disorders. In 2 FAP patients in the early stage, both high (HFC: 0.12-0.4 Hz) and low frequency components (LFC: 0.04-0.12 Hz) in the heart rate spectrum, and basic (BW) and reflex waves (RW) in the vasomotion were all markedly suppressed. However, in an FAP patient in the advanced stage, prominent spectral peaks were recognized in both the spectral bands of LFC and HFC. HFCs were neither correspondent with the respiratory frequency nor depressed by atropine, and BW was not affected by acute denervation using a local anesthetic. RW was absent irrespective of the denervation. These results suggest that the denervated heart and vascular smooth muscles might have newly acquired periodic fluctuations, although the physiological mechanism and meanings remain to be investigated.

Cephalic tetanus in a nontraumatized patient with left facial palsy

A 64-yr-old Japanese woman with a 3-day history of left facial palsy came to our pain clinic (Figure 1). She had a right facial palsy approximately 15 yr earlier that was treated by stellate ganglion block. She indicated that the current symptom was quite similar. Although her left sternocleidomastoid muscle was slightly spastic, a left stellate ganglion block was performed daily for 2 days using 5 mL of 1% lidocaine, and betamethasone 1.5 mg, vitamin B,, 1.5 mg, and adenosine triphosphate disodium 180 mg were given orally and daily. On the third day, the patient complained of dysphagia, hoarseness, and a locking jaw that began the previous afternoon. A neurologist noted left-lower-quarter facial spastic palsy and painful tonic seizure and prescribed oral carbamazepine 0.3 g daily. She did not complain of pain, and neither a wound nor an inflammatory site was evident. Therefore, the neurologist suspected an intracranial lesion and ordered a magnetic resonance image (MRI) examination. On the fourth day, the patient returned to our hospital complaining of a progressively locking jaw. As dysphagia prevented her from eating for 2 days, prompt hospitalization was considered necessary. In the early morning on the fifth day, and 7 h after admission, a convulsion occurred in the face and neck and spread to the upper part of her body. Apnea and cyanosis developed, and a nasotracheal intubation was blindly done immediately. Convulsion, however, persisted and increased. The intravenous administration of diazepam 2.5 mg was transiently effective. When the convulsion ceased, the patient showed a good level of comprehension. There was no evidence of tumor, inflammation, or cerebral vascular disease on the computed tomography scan or on the MRI. Cerebrospinal fluid examination was normal.

Resuscitation by extracorporeal lung assist of a patient suffocating after inhalation of sawdust particles.

A 17-yr-old male accidentally inhaled a massive amount of sawdust particles. Severe respiratory distress developed, resulting in subcutaneous emphysema and left pneumothorax. Therefore, sufficient positive-pressure ventilation was inapplicable. Under veno-venous extracorporeal lung assist (ECLA) with an artificial lung, the sawdust particles were removed by broncho-fibroscopy and lung lavage. After 36 h, the patient was weaned from ECLA without further complications. (Crit Care Med 1990; 18:239)

Acute respiratory failure induced by mechanical pulmonary ventilation at a peak inspiratory pressure of 40 cmH20

The effects of high pressure mechanical pulmonary ventilation at a peak inspiratory pressure of 40 cmH20 were studied on the lungs of healthy newborn pigs (14–21 days after birth). Forty percent oxygen in nitrogen was used for ventilation to prevent oxygen intoxication. The control group (6 pigs) was ventilated for 48 hours at a peak inspiratory pressure less than 18 cmH20 and a PEEP of 3–5 cmH20 with a normal tidal volume, and a respiratory rate of 20 times/min. The control group showed few deleterious changes in the lungs for 48 hours. Eleven newborn pigs were ventilated at a peak inspiratory pressure of 40 cmH20 with a PEEP of 3–5 CmH20 and a respiratory rate of 20 times/min. To avoid respiratory alkalosis, a dead space was placed in the respiratory circuit, and normocarbia was maintained by adjusting dead space volume. In all cases in the latter group, severe pulmonary impairments, such as abnormal chest roentgenograms, hypoxemia, decreased total static lung compliance, high incidence of pneumothorax, congestive atelectasis, and increased lung weight were found within 48 hours of ventilation. When the pulmonary impairments became manifest, 6 of the 11 newborn pigs were switched to the conventional medical and ventilatory therapies for 3–6 days. However, all of them became ventilator dependent, and severe lung pathology was found at autopsy. These pulmonary insults by high pressure mechanical pulmonary ventilation could be occurring not infrequently in the respiratory management of patients with respiratory failure.

To-and-fro veno-venous extracorporeal lung assist for newborns with severe respiratory distress

A veno-venous to-and-fro bypass method through a single blood access for extracorporeal lung assist with an artificial membrane lung is introduced. A premature newborn with severe respiratory distress was treated with this method. A 12 Fr. single lumen catheter with a spiral-embedded thin-wall, 0.25 mm in wall thickness, was placed in the right internal jugular vein. Venous blood was withdrawn and oxygenated blood returned alternately through the same catheter. Thus both carotid arteries and other large veins were kept intact. During the extracorporeal bypass, the patient was put on intermittent mandatory ventilation of 2 times/min for lung rest providing adequate arterial blood gases, and he survived.

Perioperative management of two patients with respiratory problems undergoing Abdominal surgery with high spinal anesthesia.

Choice of anesthetic technique; regional anesthesia vs. general anesthesia is still controversial in patients with impaired pulmonary function undergoing laparotomy. We are often concerned that positive pressure ventilation or endotracheal inhalation of dry anesthetic gases may exacerbate preexisting respiratory problems. For a patient breathing by himself preoperatively, it is the most undesirable consequence to be forced to leave an endotracheal tube for mechanically assisted ventilation for an extended time in the postoperative course. The present report describes successful perioperative management of two patients with respiratory problems undergoing abdominal surgery. We administered a combination of high spinal anesthesia for surgery and epidural analgesia for postoperative pain for the patients. Monitorings of arterial oxygen saturation with a pulse oxymeter (SP02) and endo-tidal car-

Simultaneous laser-doppler flowmetry of canine spinal cord and cerebral blood flow: Responses to\(Pa_{CO_2 } \) and blood pressure changes

AbstractWe observed the relative changes of both spinal cord blood flow (local SCBF) and local cerebral blood flow (local CBF) using independent laser-Doppler flowmeters (LDF) in 12 dogs under N2O(50%)-O2-enflurane(1.0%) anesthesia. The dorsal surface of the lumbar spinal cord and the parietal surface of the brain were partially exposed. Two fine LDF probes were placed between the exposed surfaces and the dura maters at each site. Both local SCBF and local CBF decreased simultaneously with hyperventilation and incresed with hypoventilation within several seconds. The local SCBF responses to