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The Onset of Respiration at Birth
ABSTRACTS
603
'l'he absence of this substance results in strrtctural weakness of the vessel walls. It is pointed out that this ·fragility of the walls forms the basis for the capillary fragility test, and since the fragility "is presumed to result from vitamin C deficiency, the author uses this test as an index to the patient's vitamin C reserve. It is emphasized that the dilatation of the veins and the valvular insufficiency seen in varicose veins may actually precede the reversal of the venous flow rather than follow it. Twenty-five cases of varicosities in pregnancy were studied; of this group 76 per cent showed evidence of vitamin C deficiency as determined by the fragility test. Ascorbic acid blood levels were not done because at the time of this study laboratory facilities were not available. In contrast a group of normal pregnant controls without varicosities showed that 60 per cent had normal vitamin C intake and the other 40 per cent showed only very moderate deficiency. The author conclude~ that deficiency of the C vitamin causes intracellular weakness in the vessel wall which predisposes to varicositiel'l. Increased intra-abdominal pressures may be a contributing factor. "WILLIAM BICKERS.
Newborn Harris, T. N.: Treatment of Impetigo Contagiosa With a New Preparation of Sulfathiazole, .T. A.M. A. 121: 403, 1943. The author reviews the older and well established methods of treatment of this very common disease. He mentions the oral and local treatments of the disease with various drugs and reviews the time taken in the establishment of a cure. The new method is based on a physical principle developed by Chambers. This new form of sulfonamide yields a stable suspension of fine crystals. It resembles magnesia magma in physical appearance, and remains stable in pure water for many months. When allowed to dry, the suspension does not cake, but becomes ~ fine friable powder. This new form of sulfonamide has been called "microcrystalline.'' A twenty per cent suspension of this was used. A drop or two of this suspension is applied on a piece of gauze. rrhis concentnttes the sulfonamide crystals on the surface of the dressing. The area is first washed with soap and water. On removal of the dressing 24 hours later, the lesion was found to be healed. 'rhe microcrystalline drug maintains the separation of the crystals, assuring a much greater surface for solution into local tissue fluids, and a continued distribution over the lesions. The actual time of treatment is considerably reduced. Sulfathiazole was used in these studies because of its availability and its effectivene·ss on both streptococci and staphylococci. Microcrystals of other sulfonamide compounds have been produced and would presumably be as effective against susceptible bacteria. WILLIAM BERMAN.
Barcroft, Sir Joseph: The Onset of Respiration at Birth, Lancet 2: 117, 1942. In a very stimulating essay, the author describes the development of respiratory movements as they appear in the fetus of the ewe at varying periods of development and discusses the probable mechanism of the onset of respiration. The development of movement generally and respiratory movements in particular may be divided into four stages which represent a gradual progression of activity. Stage 1.-Spasm. This appears on the thirty-fourth or thirty-fifth day, and is a single spasmatic movement of the head and neck elicited by tapping the fetus sharply between the eye and mouth in an area corresponding to the region supplied by the maxillary branch of the fifth cranial nerve. As each day ,passes this spasm expands both in the muscles involved and in the area which responds to stimulation. By the thirty-eighth day, the diaphragm may be involved.
604
AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY
Stage 2.-Rhythm. By the fortieth day, the response is a series of spasms which increase in frequency and duration. During this time the intercostal mus· cles begin to play a part. Stage 3.-Segregation. By the forty-fifth day, the initial response to stimula· tion is a general movement of the body followed by a eontinued respiratory rhythm, so that this pl1ase of the movement becomes independent. By fifty days' movement can be elicited by stimulating nearly any part of the body. Stage 4.-Inhibition. By the sixtieth day, the fetus has become inert. Very slight response follows stimulation. It remains normally quiescent until birth. The stage is set for the onset of respiration although onl.v half of the period of gestation has elapsed. The occlusion of the umbilical cord releases the inhibition and rhythmic respi· ratory movements start. Similarly if the cord is occluded during stage 3, the fetus reverts to stage 2 and in a like manner from llttage 2 to 1, and from 1 to complete cessation of movement. By transection of the central nervous system the author concludes that stage 1 can h;} reprodueed by section just above the nucleus of the twelfth nerve, stage 2 just below the pons, stage :; juHt above the pons, and stage 4 just above the posterior corpora quadrigemina. Respiratory movements from the sixtieth day on depend on a balance between inhibition and stimulation. In utero, inhibition is predominant. At birth two things happen. First, inhibition is depressed by asphyxia, and secondly, the brain is bombarded with volleys of sensation which raise the general sensitivity. The respiratory patterns which result are as follows: (1) 'file simple spasm or gasp; (2) the spasm or gasp involving the respiratory museles outlasted by a respira· tory rhythm of shallower respirations; (3) rhythms of shallow respirations which come and go, possibly not preceded by any obvious spasm; (4) the establishment of almost continuous respiration of a normal character. Which appeared would depend on the stringency of the conditions to which the fetus wM subjected. The :first would be that in which sensation was at Hs minimum and asphyxia at its maximum, the last at which sensation was at its maximum and asphyxia at its minimum. These are, what on a basis of observations in the sheep, we might expect to :ftnd in the child at birth. CARL P. HUBER.
Barnes, Allan 0., and Wilson, J. Robert: Care of the Newborn Premature Infant, J. A.M. A. 119: 545, 1942. Babies (premature) are immediately placed in Trendelenburg position, the throat cleared of mucus, placed in a warm premature jacket, and given one hundred per cent oxygen inhalations. The child is handled as little as possible. Babi:es are not weighed and bathed routinely. Axillary temperatures are taken one to two houra apart until the infants temperature is stabilized. Infants weighing less than 1,800 Gm. are given 100 per cent oxygen to decrease the respiratory effort. Occasionally a mixture of 95 per cent oxygen and 5 per cent carbon dioxide is used to stimulate respiration. No feeding is given for the first 12 to 24 hours. For the :ftrst feeding day, 5 per cent dextrose is given and then a weak evaporated milk formula, or breast milk if available. The infant is not removed from the crib for feeding until it weighs at least 2,200 Gm. Isotonic fluids may be given subcutaneously. After the first few days of life, elixir of thiamine, one drop daily, increased until eight drops are given daily. A daily dose of ten drops of an iron solution may be given. This can be followed by vitamin D and orange juice. Protein milk may be added to the formula later. An attempt is made to increase the caloric intake from 75 to 100 calories per pound of body weight. This regime resulted in a survival rate of 90.5 per cent of all viable infants whose weight was between 1,000 and 2,499 Gm.
603
'l'he absence of this substance results in strrtctural weakness of the vessel walls. It is pointed out that this ·fragility of the walls forms the basis for the capillary fragility test, and since the fragility "is presumed to result from vitamin C deficiency, the author uses this test as an index to the patient's vitamin C reserve. It is emphasized that the dilatation of the veins and the valvular insufficiency seen in varicose veins may actually precede the reversal of the venous flow rather than follow it. Twenty-five cases of varicosities in pregnancy were studied; of this group 76 per cent showed evidence of vitamin C deficiency as determined by the fragility test. Ascorbic acid blood levels were not done because at the time of this study laboratory facilities were not available. In contrast a group of normal pregnant controls without varicosities showed that 60 per cent had normal vitamin C intake and the other 40 per cent showed only very moderate deficiency. The author conclude~ that deficiency of the C vitamin causes intracellular weakness in the vessel wall which predisposes to varicositiel'l. Increased intra-abdominal pressures may be a contributing factor. "WILLIAM BICKERS.
Newborn Harris, T. N.: Treatment of Impetigo Contagiosa With a New Preparation of Sulfathiazole, .T. A.M. A. 121: 403, 1943. The author reviews the older and well established methods of treatment of this very common disease. He mentions the oral and local treatments of the disease with various drugs and reviews the time taken in the establishment of a cure. The new method is based on a physical principle developed by Chambers. This new form of sulfonamide yields a stable suspension of fine crystals. It resembles magnesia magma in physical appearance, and remains stable in pure water for many months. When allowed to dry, the suspension does not cake, but becomes ~ fine friable powder. This new form of sulfonamide has been called "microcrystalline.'' A twenty per cent suspension of this was used. A drop or two of this suspension is applied on a piece of gauze. rrhis concentnttes the sulfonamide crystals on the surface of the dressing. The area is first washed with soap and water. On removal of the dressing 24 hours later, the lesion was found to be healed. 'rhe microcrystalline drug maintains the separation of the crystals, assuring a much greater surface for solution into local tissue fluids, and a continued distribution over the lesions. The actual time of treatment is considerably reduced. Sulfathiazole was used in these studies because of its availability and its effectivene·ss on both streptococci and staphylococci. Microcrystals of other sulfonamide compounds have been produced and would presumably be as effective against susceptible bacteria. WILLIAM BERMAN.
Barcroft, Sir Joseph: The Onset of Respiration at Birth, Lancet 2: 117, 1942. In a very stimulating essay, the author describes the development of respiratory movements as they appear in the fetus of the ewe at varying periods of development and discusses the probable mechanism of the onset of respiration. The development of movement generally and respiratory movements in particular may be divided into four stages which represent a gradual progression of activity. Stage 1.-Spasm. This appears on the thirty-fourth or thirty-fifth day, and is a single spasmatic movement of the head and neck elicited by tapping the fetus sharply between the eye and mouth in an area corresponding to the region supplied by the maxillary branch of the fifth cranial nerve. As each day ,passes this spasm expands both in the muscles involved and in the area which responds to stimulation. By the thirty-eighth day, the diaphragm may be involved.
604
AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY
Stage 2.-Rhythm. By the fortieth day, the response is a series of spasms which increase in frequency and duration. During this time the intercostal mus· cles begin to play a part. Stage 3.-Segregation. By the forty-fifth day, the initial response to stimula· tion is a general movement of the body followed by a eontinued respiratory rhythm, so that this pl1ase of the movement becomes independent. By fifty days' movement can be elicited by stimulating nearly any part of the body. Stage 4.-Inhibition. By the sixtieth day, the fetus has become inert. Very slight response follows stimulation. It remains normally quiescent until birth. The stage is set for the onset of respiration although onl.v half of the period of gestation has elapsed. The occlusion of the umbilical cord releases the inhibition and rhythmic respi· ratory movements start. Similarly if the cord is occluded during stage 3, the fetus reverts to stage 2 and in a like manner from llttage 2 to 1, and from 1 to complete cessation of movement. By transection of the central nervous system the author concludes that stage 1 can h;} reprodueed by section just above the nucleus of the twelfth nerve, stage 2 just below the pons, stage :; juHt above the pons, and stage 4 just above the posterior corpora quadrigemina. Respiratory movements from the sixtieth day on depend on a balance between inhibition and stimulation. In utero, inhibition is predominant. At birth two things happen. First, inhibition is depressed by asphyxia, and secondly, the brain is bombarded with volleys of sensation which raise the general sensitivity. The respiratory patterns which result are as follows: (1) 'file simple spasm or gasp; (2) the spasm or gasp involving the respiratory museles outlasted by a respira· tory rhythm of shallower respirations; (3) rhythms of shallow respirations which come and go, possibly not preceded by any obvious spasm; (4) the establishment of almost continuous respiration of a normal character. Which appeared would depend on the stringency of the conditions to which the fetus wM subjected. The :first would be that in which sensation was at Hs minimum and asphyxia at its maximum, the last at which sensation was at its maximum and asphyxia at its minimum. These are, what on a basis of observations in the sheep, we might expect to :ftnd in the child at birth. CARL P. HUBER.
Barnes, Allan 0., and Wilson, J. Robert: Care of the Newborn Premature Infant, J. A.M. A. 119: 545, 1942. Babies (premature) are immediately placed in Trendelenburg position, the throat cleared of mucus, placed in a warm premature jacket, and given one hundred per cent oxygen inhalations. The child is handled as little as possible. Babi:es are not weighed and bathed routinely. Axillary temperatures are taken one to two houra apart until the infants temperature is stabilized. Infants weighing less than 1,800 Gm. are given 100 per cent oxygen to decrease the respiratory effort. Occasionally a mixture of 95 per cent oxygen and 5 per cent carbon dioxide is used to stimulate respiration. No feeding is given for the first 12 to 24 hours. For the :ftrst feeding day, 5 per cent dextrose is given and then a weak evaporated milk formula, or breast milk if available. The infant is not removed from the crib for feeding until it weighs at least 2,200 Gm. Isotonic fluids may be given subcutaneously. After the first few days of life, elixir of thiamine, one drop daily, increased until eight drops are given daily. A daily dose of ten drops of an iron solution may be given. This can be followed by vitamin D and orange juice. Protein milk may be added to the formula later. An attempt is made to increase the caloric intake from 75 to 100 calories per pound of body weight. This regime resulted in a survival rate of 90.5 per cent of all viable infants whose weight was between 1,000 and 2,499 Gm.