Anatomical considerations in sternal puncture

The thickness of the manubrium, the width and thickness of the body of the sternum at the level of second intercostal space as well as the thickness of the spongiosa and outer and inner compact layers have been measured in 67 human cadavers. Consequently, it is recommended that sternal puncture be made at the level of the second intercostal space in the adult and at the manubrium in children. Depth of puncture should not exceed 4 mm. Sternal puncture can thereby be done with greater confidence of avoiding penetration of the sternum, a potentially serious complication.     

Intercostal catheter analgesia is more efficient vs. intercostal nerve blockade for post-thoracotomy pain relief

A pain after thoracotomy may result in a postoperative hypoventilation and lead to atelectases and pneumonia. This study was aimed to compare two analgesic regimens after posterolateral thoracotomy. 80 patients (40-70 years) undergoing thoracotomy were randomized to intercostal catheter analgesia (group A, n = 40) and intercostal nerve block (group B, n = 40). Patients in group A were given 20 mL of 0.5% bupivacaine injections twice a day by intercostal catheter. Intercostal nerve blockade was performed using 5 mL of 0.5% bupivacaine. Intercostal nerve in thoracotomy wound, nerves below and above thoracotomy wound was also injected. PaO2, PaCO2, FVC, FEV1 and visual analog pain scale (VAS) were obtained preoperatively, 24, 48 and 72 hours after operation. Postoperative complications were recorded at the patient discharge. Differences between groups were calculated using Mann-Whitney, KW test and chi square test. The arterial blood gas analyses did not show statistically significant change in any group and time according to the baseline values. FVC and FEV1 decreased significantly in both groups at first postoperative day according to baseline measurements. Patients in B group had significantly higher FEV1 values in the third postoperative day (73.05 +/- 11.25 in A vs. 83.50 +/- 9.17 in B group, p < 0.05). Intercostal catheter analgesia resulted in significantly lower postoperative VAS scores and reduced opioid requirement as compared to intercostal nerve blockade. No differences in the postoperative complications were observed between groups.     

Respiratory muscle activity measured with a noninvasive EMG technique: technical aspects and reproducibility.

A new method is being developed to investigate airway obstruction in young children by means of noninvasive electromyography (EMG) of diaphragmatic and intercostal muscles. The purpose of this study was to evaluate the reproducibility of the EMG measurements. Eleven adults, 39 school children (20 healthy, 19 asthmatic), and 16 preschool children were studied during tidal breathing on separate occasions: two for adults with a time interval of 3 wk and three for children with time intervals of 1 and 24 h. Single electrodes were placed on the second intercostal space left and right of the sternum and at the height of the frontal and the dorsal diaphragm. Bipolar electrode pairs were placed on the rectus abdominis muscle. A newly designed digital physiological amplifier without any analog filtering was used to measure the EMG signals. Except for the average dorsal diaphragm EMG derivation in healthy school children on the second occasion, a significant correlation between the mean peak-to-peak inspiratory activity of average diaphragmatic and intercostal EMG was found in the different age groups on the different measurement occasions (P < 0.05). To assess the repeatability, we described the agreement between the repeated measurements within the same subjects. No significant differences were found between the measurements on the separate occasions. Our observations indicate that the EMG signals derived from the diaphragm and intercostal muscles are, in different age groups with and without asthma, reproducible during tidal breathing.     

Post-operative analgesia following thoracotomy in the dog: an evaluation of the effects of bupivacaine intercostal nerve block and nalbuphine on respiratory function.

Pain following thoracotomy reduces pulmonary ventilation in man and a similar effect is believed to occur in animals. The effects of two analgesic regimens on arterial blood gas parameters were studied in dogs following thoracotomy. Post-Operative analgesia was provided with intermittent nalbuphine, either alone or in combination with an intercostal nerve block using bupivacaine. Arterial blood gas analysis was carried out at 4, 8 and 16 h post-operatively, both before the administration of nalbuphine and again 30 min later. Animals which received nalbuphine alone had a significant rise in arterial oxygenation following administration of this analgesic. This effect was not observed at 4 and 8 h post-operatively in dogs which had an intercostal block with bupivacaine, but was seen at 16 h post-operatively when it could be anticipated that the effects of bupivacaine would have waned. These results suggest that intercostal block with bupivacaine can provide analgesia for over 8 h, and that the duration of action of nalbuphine in controlling post-operative pain in the dog is probably less than 4 h.     

Age and individual variability of aortic valve structure in man

In persons of both sex at the age beginning from birth up to 90 years. 275 aortal valves have been investigated. A morphological classification of the valves has been suggested depending on peculiarities of their structure and main dimentions: valves with the valvula surfaces looking as a part of a spheroid, ellipsoid, or having a stepwise, cochliowise form; according to the mode of the valvula closure when the valve is closed: with straight, arched and wavy lines of closure; according to the size: valves with predominant dimentions of one valvula when two others are equal, valves with two equal valvulae and both are larger than the third one, valves with equal valvulae, valves with three different valvulae. Distribution of various types of the valves in accordance with the given classification is determined, the most frequently occurring forms are demonstrated. The valvulae grow in different directions unevenly and asynchronously with the aortal ostium growth, therefore during certain age periods a probability on a nonhermetic valve increases, especially from 1 up to 3 and from 56 up to 70 years of age.     

Computed tomography or necropsy diagnosis of multiple bullae and the treatment of pneumothorax in rhesus macaques (Macaca mulatta)

Pulmonary bullae and pneumothorax have various etiologies in veterinary medicine. We diagnosed multiple pulmonary bullae combined with or without pneumothorax by computed tomography (CT) or necropsy in seven rhesus macaques (Macaca mulatta) imported from China. Two of seven rhesus macaques accompanied by pneumothorax were cured by fixation of ruptured lung through left or right 3rd intercostal thoracotomy. Pneumonyssus simicola, one of the etiologies of pulmonary bullae, was not detected from tracheobronchiolar lavage. To the best of our knowledge, this is the first case report on the CT‐aided diagnosis of pulmonary bullae and the successful treatment of combined pneumothorax by thoracotomy in non‐human primates (NHPs).     

Internal mammary vessels as a model for power Doppler imaging of recipient vessels in microsurgery.

The aim of this interdisciplinary study was to evaluate power Doppler imaging as a method of collecting reliable preoperative data concerning the diameters and topography of exemplary internal mammary vessels as recipient vessels in reconstructive microsurgery. Thirteen female patients (range, 37 to 58 years; mean, 45.6 years) were examined preoperatively with power Doppler imaging from the first to the fifth intercostal space parasternally and bilaterally. These data are compared with measurements obtained intraoperatively in each individual. Mean velocity in the artery in the second intercostal space on the right side is 47.11 cm/sec (range, 15 to 90 cm/sec) and on the left side is 42.25 cm/sec (range, 18 to 95 cm/sec). Mean velocity in the vein in the second intercostal space on the right side is 17.80 cm/sec (range, 10 to 30 cm/sec) and on the left side is 13.06 cm/sec (range, 5.3 to 32 cm/sec). The topographic results are in close agreement with intraoperative measurements and previous anatomical studies. Sonographic preoperative data of arteries (mean, 1.88 mm) show slightly smaller diameters than intraoperative measurements (mean, 2.08 mm), whereas veins show slightly larger diameters in sonography (mean, 2.33 mm) than intraoperatively (mean, 2.12 mm). Mean sonographic diameter of artery ranges from 2.14 mm (second intercostal space) to 1.46 mm (fifth intercostal space), of the vein from 2.76 (second intercostal space) to 1.25 mm (fifth intercostal space). In one case, a vein was not detectable. This noninvasive method leads to confirmation of the preoperative choice of the optimal recipient vessels for free tissue transfer and does not harm the patient.     

The transduction properties of intercostal muscle mechanoreceptors

Background  

Intercostal muscles are richly innervated by mechanoreceptors. In vivo studies of cat intercostal muscle have shown that there are 3 populations of intercostal muscle mechanoreceptors: primary muscle spindles (1°), secondary muscle spindles (2°) and Golgi tendon organs (GTO). The purpose of this study was to determine the mechanical transduction properties of intercostal muscle mechanoreceptors in response to controlled length and velocity displacements of the intercostal space. Mechanoreceptors, recorded from dorsal root fibers, were localized within an isolated intercostal muscle space (ICS). Changes in ICS displacement and the velocity of ICS displacement were independently controlled with an electromagnetic motor. ICS velocity (0.5 – 100 μm/msec to a displacement of 2,000 μm) and displacement (50–2,000 μm at a constant velocity of 10 μm/msec) parameters encompassed the full range of rib motion.     

Anatomy and topography of external iliac lymph nodes in adults]

The investigation of the external iliac lymph nodes has been performed in 152 preparations of corpses of mature persons of both sex, who died from causes not connected with any disease of the lymphatic system, lower extremities and pelvic organs. The external iliac lymph nodes and their afferent and efferent lymphatic vessels have been revealed by means of interstitial injection of the lower extremities and pelvic organs, as well as by means of direct injection of Gerota mass into the lymphatic vessels. Form, amount, dimensions and topography of common iliac lymph nodes have been studied. Lymphatic vessels, running from certain parts and organs of the body to various subgroups of the external iliac lymph nodes have been described, as well as efferent lymph vessels of these nodes. The external iliac lymph nodes are constant formations; the largest of them--lymph nodes of the lacuna--are nodes of the I step for the lower extremity lymph vessels. In 54% of cases in persons of both sex positive (right-sided) asymmetry has been revealed. Total amount of the iliac lymph nodes prevails in men, while their size is greater in women. The size of these nodes in persons of both sex is greater to the left than to the right. There are connections (in 3% of cases) between the external iliac lymph nodes and aortal and lumbar nodes of the opposite side.     

Topography of the aorto-iliac fragment and the ilio-caval confluence in man

By means of selective injection of blood vessels with water suspension of red lead and subsequent angiography, topography of the aortal bifurcation in the area of the vena cava formation has been studied in corpses of persons of both sex at the age 25-102 years and in 100 corpses of fetuses (the second half of pregnancy). Position, diameters of the arteries and veins situating in these areas, as well as branching or connection angles of the vessels are directly dependent on age. The data obtained on topography of the blood vessels and on their interrelations with position of the ureters and between themselves are of essential importance for operative approaches to the pelvic organs.     

Cryoanalgesia for relief of pain after thoracotomy.

One hundred patients undergoing thoracotomy had their intercostal nerves blocked by cryoanalgesia before closure and the effect of this on their postoperative pain was evaluated. Of the 100 patients, 79 were free of pain, 12 had some discomfort, and nine reported severe pain necessitating narcotic analgesia (mean 1.5 injections per patient). Only five patients needed assisted removal of sputum, though eight showed retention of sputum or subsegmental collapse of lung radiographically. Overall, lack of pain and greater alertness much enhanced the value of physiotherapy, which resulted in a low incidence of complications and a smooth recovery. The technique of cryoanalgesia is simple, extremely effective, and apparently offers benefits not conferred by other methods of preventing pain after thoracotomy.     

The origin and pattern of distribution of the posterior intercostal arteries in the baboon (Papio ursinus)

The posterior intercostal arteries of six female and four adult male baboons (Papio ursinus) were investigated by latex injection and subsequent dissection to determine their origin and pattern of distribution. Basic morphological and functional similarities with that of man could provide some base-line data pertinent to future experimental studies in the areas of thoracic aortic aneurysm and aortic atherosclerotic lesion in man. Basic similarities were observed between the baboon and man in the number of intersegmental arteries, the origin of the first two pairs of posterior intercostal arteries, and the anastomosis between the superior intercostal and the third posterior intercostal arteries. However, the baboon showed a craniocaudal sequence of paired orifices giving rise to paired arteries; orifices with incompletely divided septum giving rise to paired arteries; single orifices leading to a common trunk, which finally gives rise to paired arteries; and single orifices opening into single arteries. In addition, there was a craniocaudal decrease in the distance between any given pair of intercostal arteries and an increase in the spacing between adjacent pairs of intercostal arteries. Where a single artery supplied one side of the intercostal space, the contralateral side received a collateral branch, either from the preceding or succeeding intercostal artery. Though the basic organisation of the origin and distribution of the posterior intercostal arteries in the baboon is similar to that of man, the differences observed in the baboon might be attributed to factors such as body size, mode of activity, and even the phylogenetic level of development of the baboon.     

The Prevalence of Ventricular Septal Defect in Elementary School Children in the City of Toronto

A knowledge of the prevalence of ventricular septal defect in different age groups is basic to the estimation of all complications of this disease. The Cardiac Registry in the City of Toronto has provided this information for elementary school children. Clinical diagnosis of ventricular septal defect was made if the child had a pansystolic murmur in the 3rd or 4th left intercostal space with a palpable thrill and/or electrocardiographic evidence of ventricular hypertrophy and/or radiologic evidence of pulmonary plethora at one or more examinations. When possible, the diagnosis was confirmed by cardiac catheterization. Children with the same murmur, no thrill and normal electrocardiogram and radiograph were labelled “probable” and presumed to have a minute or disappearing defect.The prevalence rate of ventricular septal defect in elementary school children varied betwen 0.44 and 0.48 per 1000 in four successive years of study. The rate of “probable” ventricular septal defect varied between 0.27 and 0.37 per 1000 children.     

Respiratory muscle activity in the assessment of bronchial responsiveness in asthmatic children

We investigatedwhether an increase in transcutaneous electromyographic (EMG) activityof the diaphragm and intercostal muscles corresponds with theconcentration of histamine that induces a 20% fall in the forcedexpiratory volume in one second(FEV₁; PC₂₀). Eleven asthmatic children(mean age 11.9 yr) were studied after they were given histaminechallenge. EMG activity atPC₂₀ or at the highest histamineconcentration was compared with activity at baseline by calculating theratio of the mean peak-to-peak excursion at the highest histamine doseto that at baseline [EMG activity ratio (EMGAR)]. In allchildren reaching PC₂₀, anincrease in diaphragmatic and intercostal EMGAR was observed. Noincrease was found at the dose step beforePC₂₀ was reached. In sixchallenges, no fall in FEV₁ wasinduced, and no increase in EMGAR was seen. In two challenges, no fallin FEV₁ was induced, but increasein diaphragmatic or intercostal EMGAR was observed. Increase in the electrical activity of the diaphragm and intercostal muscles in asthmatic children corresponds closely to a 20% fall inFEV₁ induced by histaminechallenge.

     

A Murine Closed-chest Model of Myocardial Ischemia and Reperfusion

Surgical trauma by thoracotomy in open-chest models of coronary ligation induces an immune response which modifies different mechanisms involved in ischemia and reperfusion. Immune response includes cytokine expression and release or secretion of endogenous ligands of innate immune receptors. Activation of innate immunity can potentially modulate infarct size. We have modified an existing murine closed-chest model using hanging weights which could be useful for studying myocardial pre- and postconditioning and the role of innate immunity in myocardial ischemia and reperfusion. This model allows animals to recover from surgical trauma before onset of myocardial ischemia.Volatile anesthetics have been intensely studied and their preconditioning effect for the ischemic heart is well known. However, this protective effect precludes its use in open chest models of coronary artery ligation. Thus, another advantage could be the use of the well controllable volatile anesthetics for instrumentation in a chronic closed-chest model, since their preconditioning effect lasts up to 72 hours. Chronic heart diseases with intermittent ischemia and multiple hit models are other possible applications of this model.For the chronic closed-chest model, intubated and ventilated mice undergo a lateral blunt thoracotomy via the 4th intercostal space. Following identification of the left anterior descending a ligature is passed underneath the vessel and both suture ends are threaded through an occluder. Then, both suture ends are passed through the chest wall, knotted to form a loop and left in the subcutaneous tissue. After chest closure and recovery for 5 days, mice are anesthetized again, chest skin is reopened and hanging weights are hooked up to the loop under ECG control.At the end of the ischemia/reperfusion protocol, hearts can be stained with TTC for infarct size assessment or undergo perfusion fixation to allow morphometric studies in addition to histology and immunohistochemistry.     

Linkage between parasternals and external intercostals during resting breathing

To assess the mechanical coupling between the parasternal and external intercostals in the cranial portion of the rib cage, we measured the respiratory changes in length and the electromyograms of the two muscles in the same third or fourth intercostal space in 24 spontaneously breathing dogs. We found that 1) the amount of inspiratory shortening of the external intercostal was considerably smaller than the amount of shortening of the parasternal; 2) after selective denervation of the parasternal, the inspiratory shortening of both the parasternal and the external intercostal was almost abolished; 3) on the other hand, after selective denervation of the external intercostal, the inspiratory shortening of the parasternal was unchanged, and the inspiratory shortening of the external intercostal was reduced but not suppressed; and 4) this persistent shortening of the external intercostal was reversed into a clear-cut inspiratory lengthening when the parasternal was subsequently denervated. We conclude that in the dog 1) the inspiratory contraction of the external intercostals in the cranial portion of the rib cage is agonistic in nature as is the contraction of the parasternals; 2) during resting breathing, however, the changes in length of these external intercostals are largely determined by the action of the parasternals. These observations are consistent with the idea that in the dog, the parasternals play a larger role than the external intercostals in elevating the ribs during resting inspiration.     

急性大鼠心肌梗死实验模型的制备

目的建立一种稳定可重复的急性心肌梗死动物模型。方法Wistar大鼠经戊巴比妥钠麻醉后,气管切开插管,连通呼吸机,开胸后结扎左冠状动脉前降支。4周后取出心脏做病理组织学和心肌特异性肌钙蛋白T免疫组织化学染色检测。结果成功制备心肌梗死动物模型,并进行了病理组织学和免疫组织化学染色证实。结论本建立的实验方法操作简单,成功率高,结果可靠。     

Respiratory pattern changes produced by intercostal muscle/rib vibration

Large-amplitude vibration of the intercostal muscles/ribs has an inhibitory effect on inspiratory motor output. This effect has been attributed, in part, to the stimulation of intercostal muscle tendon organs. Intercostal muscle/rib vibration can also produce a decrease or increase in respiratory frequency. Studies were conducted 1) to determine whether, in addition to intercostal tendon organs, costovertebral joint mechanoreceptors (CVJR's) contribute to the inspiratory inhibitory effect of intercostal muscle/rib vibration (IMV) and 2) to explain the different respiratory frequency responses to IMV previously reported. Phrenic (C5) activity was monitored in paralyzed thoracotomized, artificially ventilated cats. Vibration (125 Hz) at amplitudes greater than 1,200 micron of one T6 intercostal space in decerebrated vagotomized rats reduced phrenic activity. This response was still present but weaker in some animals after denervation of the T6 intercostal muscles. Subsequent denervation of the T6 CVJR's by dorsal root sections eliminated this effect. Respiratory frequency decreased during simultaneous vibration (greater than 1,200 micron) of the T5 and T7 intercostal spaces in vagotomized cats. Respiratory frequency increased during IMV of two intercostal spaces (greater than 1,300 micron) in vagal intact cats. The use of different anesthetics (pentobarbital, allobarbital) did not alter these results. We conclude that CVJR's may contribute to the inhibitory effect of IMV on medullary inspiratory activity. The presence or absence of pulmonary vagal afferents can account for the different respiratory frequency responses to IMV, and different anesthetics did not influence these results.     

Age characteristics of the projections of the heart and its foramina on the anterior thoracic wall in newborn infants and children younger than 7 years of age

Projections of the heart borders and its orifices on the anterior thoracic wall have been studied in 122 corpses of newborns and children up to 7 years of age by means of visiography, dioptrography and preparation methods. In parallel with changes occurring in the cardiac borders, projections of the vena cava, the pulmonary trunk orifices, as well as projections of both atrioventricular orifices change, too. The level of their projections is gradually going down. For example, in the pulmonary trunk orifices from the II rib level drops down to the III rib, the aortic orifices--from the II rib level down to the IV rib, the right atrioventricular orifice--from the III rib level down to the V rib, and the left one--from the III rib level down to the IV intercostal level. While the child is growing, the heart is turning around the sagittal, vertical and frontal axis. Department of Operative Surgery and Topographic Anatomy, M. I. Kalinin Medical Institute, Andizhan.