Need For Respiratory Assistance Research Articles

Comparative Study on the Clinical Characteristics of Transient Tachypnea of Newborns according to the Need for Invasive Mechanical Ventilation

Purpose: Transient tachypnea of the newborn (TTN) is the most prevalent respiratory disease worldwide. Many neonates with TTN generally demonstrate spontaneous improvement. However, only few patients present with severe complications. This study aimed to investigate the differences in clinical features to identify neonates at risk for further complications.Methods: Between January 2015 and December 2020, 267 neonates who developed dyspnea within 6 h of birth were delivered at a gestational age of at least 37 weeks. The experimental group (group E) included 44 neonates who required invasive mechanical ventilation, whereas the control group (group C) included 223 neonates who required only observation or non-invasive respiratory support. We analyzed the differences in clinical and perinatal factors between the two groups.Results: Gestational age and pH on arterial blood gas analysis at admission were significantly lower in group E (<i>p</i><0.05). Clinical findings, such as moaning, tachypnea (>90 breaths/min), and pneumothorax, were more frequently observed in group E (<i>p</i><0.05).Conclusion: Moaning, tachypnea (>90 breaths/min), and need for respiratory assistance (fraction of inspired oxygen concentration ≥0.25) are predictive factors for increased risk of progression to a more severe disease course in neonates with TTN. Additional studies are needed to identify definitive factors that can differentiate TTN that improves spontaneously from TTN that requires intensive care.

Early lung ultrasound score to predict noninvasive ventilation needing in neonates from 33 weeks of gestational age: A multicentric study.

To propose an early lung ultrasound (LUS) score for the prediction of the need for respiratory assistance in newborns of gestational age (GA) ≥ 33 weeks presenting respiratory distress. Multicenter, prospective observational study in third-level neonatal intensive care units. Infants with GA ≥ 33 + 0 weeks with respiratory distress within 3 h of life. Three LUS for each patient were collected: within 3 h of life (T0), at 4-6 h of life (T1), and at the resolution of symptoms (T2). The primary aim was to assess the validity of the early LUS score in predicting the need for continuous positive airway pressure(CPAP). We also evaluated the validity of the score in predicting the need for surfactant, the scores' trend in our population, and any correlation with the duration of ventilation and oxygen therapy. Sixty-two patients were enrolled in the study. The mean GA was 36 weeks. The receiver operating characteristic analysis for the LUS T0 and T1 yielded area under the curves of 0.91 and 0.82 in predicting the need for CPAP, respectively. LUS score cut off of 6 (sensitivity 84.8%, specificity 86.2%) and 5 (sensitivity 66.7%, specificity 100%) were calculated at T0 and T1, respectively. We found significant correlations between LUS score and respiratory assistance, surfactant administration, and SpO2 /FiO2 ratio. An early LUS score is a good noninvasive predictor of the need for respiratory assistance with CPAP and surfactant administration in newborns with GA ≥ 33 weeks.

Mortality in Neuromuscular Early Onset Scoliosis Following Spinal Deformity Surgery.

The purpose of this study was to report mortality and associated risk factors in neuromuscular early onset scoliosis following spinal deformity surgery. This is a multicenter retrospective cohort study of patients with cerebral palsy (CP), spinal muscular atrophy, myelodysplasia, muscular dystrophy, or myopathy undergoing index spine surgery from 1994 to 2020. Mortality risk was calculated up to 10 years postoperatively. Proportional hazard modeling was utilized to investigate associations between risk factors and mortality rate. A total of 808 patients [mean age 7.7 y; 439 (54.3%) female] were identified. Postoperative 30-day, 90-day, and 120-day mortality was 0%, 0.001%, and 0.01%, respectively. 1-year, 2-year, 5-year, and 10-year mortality was 0.5%, 1.1%, 5.4%, and 17.4%, respectively. Factors associated with increased mortality rate: CP diagnosis [hazard ratio (HR): 3.14, 95% confidence interval (CI): 1.71; 5.79, P<0.001]; nonambulatory status (HR: 3.01, 95% CI: 1.06; 8.5, P=0.04)]; need for respiratory assistance (HR: 2.17, 95% CI: 1.00; 4.69, P=0.05). In neuromuscular patients with early onset scoliosis, mortality risk at 10 years following spine surgery was 17.4%. As mortality was 1.1% at 2 years, premature death was unlikely a direct result of spine surgery. Diagnosis (CP) and markers of disease severity (nonambulatory status, respiratory assistance) were associated with increased mortality rate. Prognostic level II.

Airway anomalies in paediatric congenital heart diseases: Utility of bedside fibreoptic flexible bronchoscopy

Background : Acute respiratory diseases are common neonatal conditions leading to neonatal intensive care unit admissions (NICU). Noisy respiration with increased work of breathing, persistent need for respiratory assistance and persistent radiological opacities prompts evaluation by fibreoptic flexible bronchoscopy (FFB). FFB has several benefits in neonates, however, this modality is not widely used due to lack of expertise or non-availability of equipment. We present our 7 years of experience with neonatal FFB. Methods : A retrospective, medical chart search study was conducted at a tertiary care multispecialty hospital, in neonates who underwent FFB over a period of 7 years (2011-2017). Results : Total 88 bronchoscopies were performed in 83 neonates admitted in the NICU. Median birth weight and gestational age were 2600 grams (range 820- 3660) and 37 weeks (range 26-41). Median age at the time of FFB was 27.5 days (range 1-152). While 51 procedures were done transnasally, 37 bronchoscopies were done through endotracheal tube. Most common co-morbid condition noted was congenital heart diseases (20.4%). Indications included persistent oxygen requirement (32/88) lung collapse (21/88), stridor (27/88), extubation failure (4/88), recurrent apnea (2/88) and suspected airway anomaly (2/88). Tracheobronchitis (8/32) and tracheobronchomalacia (8/32) were the common findings in neonates with prolonged oxygen requirement. Most common cause of stridor in neonates was laryngomalacia (16/27) followed by subglottic stenosis (4/27). Myriad of congenital airway anomalies could be diagnosed by FFB including laryngomalacia (18/88) choanal atresia (4/88), laryngeal cleft (4/88), tracheoesophageal fistula (TEF) (4/88), and one each of pyriform stenosis, laryngeal web, vocal cord paresis, absent tracheal ring and complete tracheal rings. Radiological improvement was seen in 17/21 (80.9%) cases of lung collapse after FFB. Bronchoalveolar lavage was done in 52 procedures, and microbiological yield was obtained in 16 (30.7%). Change in medical management by either, adding systemic steroids or changing antibiotics, after FFB was done in 35/88 occasions. Surgical intervention were undertaken in 15 cases (17%), including tracheostomies (9/15), TEF repair (4/15), lateralization of vocal cord (1/15), excision of laryngeal web (1/15). Transient hypoxemia was seen in (4/88) occasions while 83/88 cases did not suffer any complications. Conclusion : Airway anomalies are common in newborns and their early detection by FFB can be beneficial for optimum management. FFB can be used as an important diagnostic tool that can guide medical and surgical interventions in NICU.

Airway anomalies detected in neonates by fibreoptic flexible bronchoscopy: Experience of 7 years

Background : Acute respiratory diseases are common neonatal conditions leading to neonatal intensive care unit admissions (NICU). Noisy respiration with increased work of breathing, persistent need for respiratory assistance and persistent radiological opacities prompts evaluation by fibreoptic flexible bronchoscopy (FFB). FFB has several benefits in neonates, however, this modality is not widely used due to lack of expertise or non-availability of equipment. We present our 7 years of experience with neonatal FFB. Methods : A retrospective, medical chart search study was conducted at a tertiary care multispecialty hospital, in neonates who underwent FFB over a period of 7 years (2011-2017). Results : Total 88 bronchoscopies were performed in 83 neonates admitted in the NICU. Median birth weight and gestational age were 2600 grams (range 820- 3660) and 37 weeks (range 26-41). Median age at the time of FFB was 27.5 days (range 1-152). While 51 procedures were done transnasally, 37 bronchoscopies were done through endotracheal tube. Most common co-morbid condition noted was congenital heart diseases (20.4%). Indications included persistent oxygen requirement (32/88) lung collapse (21/88), stridor (27/88), extubation failure (4/88), recurrent apnea (2/88) and suspected airway anomaly (2/88). Tracheobronchitis (8/32) and tracheobronchomalacia (8/32) were the common findings in neonates with prolonged oxygen requirement. Most common cause of stridor in neonates was laryngomalacia (16/27) followed by subglottic stenosis (4/27). Myriad of congenital airway anomalies could be diagnosed by FFB including laryngomalacia (18/88) choanal atresia (4/88), laryngeal cleft (4/88), tracheoesophageal fistula (TEF) (4/88), and one each of pyriform stenosis, laryngeal web, vocal cord paresis, absent tracheal ring and complete tracheal rings. Radiological improvement was seen in 17/21 (80.9%) cases of lung collapse after FFB. Bronchoalveolar lavage was done in 52 procedures, and microbiological yield was obtained in 16 (30.7%). Change in medical management by either, adding systemic steroids or changing antibiotics, after FFB was done in 35/88 occasions. Surgical intervention were undertaken in 15 cases (17%), including tracheostomies (9/15), TEF repair (4/15), lateralization of vocal cord (1/15), excision of laryngeal web (1/15). Transient hypoxemia was seen in (4/88) occasions while 83/88 cases did not suffer any complications. Conclusion : Airway anomalies are common in newborns and their early detection by FFB can be beneficial for optimum management. FFB can be used as an important diagnostic tool that can guide medical and surgical interventions in NICU.

Patients with ANCA-associated vasculitis admitted to the intensive care unit with acute vasculitis manifestations: a retrospective and comparative multicentric study

PurposeData for ANCA-associated vasculitis (AAV) patients requiring intensive care are scarce.MethodsWe included 97 consecutive patients with acute AAV manifestations (new onset or relapsing disease), admitted to 18 intensive care units (ICUs) over a 10-year period (2002–2012). A group of 95 consecutive AAV patients with new onset or relapsing disease, admitted to two nephrology departments with acute vasculitis manifestations, constituted the control group.Results In the ICU group, patients predominantly showed granulomatosis with polyangiitis and proteinase-3 ANCAs. Compared with the non-ICU group, the ICU group showed comparable Birmingham vasculitis activity score and a higher frequency of heart, central nervous system and lungs involvements. Respiratory assistance, renal replacement therapy and vasopressors were required in 68.0, 56.7 and 26.8% of ICU patients, respectively. All but one patient (99%) received glucocorticoids, 85.6% received cyclophosphamide, and 49.5% had plasma exchanges as remission induction regimens. Fifteen (15.5%) patients died during the ICU stay. The following were significantly associated with ICU mortality in the univariate analysis: the need for respiratory assistance, the use of vasopressors, the occurrence of at least one infection event in ICU, cyclophosphamide treatment, sequential organ failure assessment at admission and simplified acute physiology score II. After adjustment on sequential organ failure assessment or infection, cyclophosphamide was no longer a risk factor for mortality. Despite a higher initial mortality rate of ICU patients within the first hospital stay (p < 0.0001), the long-term mortality of hospital survivors did not differ between ICU and non-ICU groups (18.6 and 20.4%, respectively, p = 0.36). Moreover, we observed no renal survival difference between groups after a 1-year follow-up (82.1 and 80.5%, p = 0.94).ConclusionThis study supports the idea that experiencing an ICU challenge does not impact the long-term prognosis of AAV patients.

Monitored anesthesia care for great saphenous vein stripping surgery with target controlled infusion of propofol and remifentanil: a prospective study.

BackgroundThe aim of this study was to determine the appropriate target concentrations at the effect site of propofol and remifentanil when deep sedation was achieved by monitored anesthesia care (MAC) anesthesia and related respiratory depression during vein stripping surgery for varicose veins.MethodsIn total, 51 adult patients who were scheduled for varicose vein stripping surgery were sedated with propofol and remifentanil during the surgery, after administration of midazolam. Target concentrations at the effect site of the two drugs were changed based on the patient's status. Respiratory support was applied in the order of oxygen supply, chin lift, and assisted mask ventilation. Target concentrations at the effect site of propofol and remifentanil, the need for respiratory support, and a six-point rating scale satisfaction score were the outcome measurements.ResultsOnly one patient did not require oxygen, eight patients needed oxygen alone, 22 patients required use of the chin lift technique, and 20 patients were assisted with mask ventilation. There was no significant difference in the target concentration of propofol or remifentanil between the patients who required mask ventilation and those who did not. Fifty of the 51 patients reported a satisfaction score of 6.ConclusionsAlthough MAC using low target concentrations of propofol and remifentanil during vein stripping surgery was satisfactory to patients, close observation regarding the need for respiratory assistance was necessary.

Association between moderate–severe bronchiolitis and syndrome of inappropriate antidiuretic hormone secretion in emergency departments

Abstract Objectives To identify clinical characteristics that may lead to the early identification of patients hospitalised for moderate-to-severe bronchiolitis with urine results associated with the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Patients and methods A prospective observational study was conducted, spanning the bronchiolitis epidemic season (October 2012–March 2013), including all children who were hospitalised with a diagnosis of moderate-to-severe bronchiolitis. The following criteria were used to establish a diagnosis of SIADH: urine sodium level of 40 mmol/L or greater, urine osmolarity above 500 mosm/kg, and urine density of 1020 g/L or greater. Demographic characteristics, ventilation mode and clinical outcome were also analysed. A comparison was made between patients that met urine SIADH criteria and those that did not. Results A total of 126 children were included, 23 (18.6%) with urine SIADH criteria. Patients in this group had a higher incidence of pneumonia and/or atelectasis on chest X-ray (21.7% vs. 1.9%, p = .002), worse response to bronchodilator treatment with nebulised adrenaline (69.5% vs. 28,1%, p = .016), more need for respiratory assistance (high flow oxygen therapy (17.4% vs. 7.7%, p = .016)), or non-invasive mechanical ventilation (13% vs. 5.8%, p = .034), and more admissions to the PICU (26.1% vs. 6.8%, p = .007). Conclusions Patients older than 1 month with acute moderate bronchiolitis and urine SIADH criteria present poorer progress and greater need for non-invasive mechanical ventilation, PICU admission, and a higher incidence of pneumonia on chest X-ray. For this reason, urine samples should be collected from these patients for early diagnosis of SIADH, and thus early treatment of fluid and electrolyte abnormalities.

Asociación entre bronquiolitis moderada-grave y síndrome de secreción inadecuada de hormona antidiurética en urgencias

ObjectivesTo identify clinical characteristics that may lead to the early recognition of patients admitted to the hospital for moderate-to-severe bronchiolitis with urine results associated with the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Patients and methodsA prospective observational study was conducted, spanning the bronchiolitis epidemic season (October 2012-March 2013), including all children who were admitted to the hospital with a diagnosis of moderate-to-severe bronchiolitis. The following criteria were used to establish a diagnosis of SIADH: urine sodium level of 40mmol/L or greater, urine osmolarity above 500 mosm/Kg, and urine density of 1020g/L or greater. Demographic characteristics, ventilation mode and clinical outcome were also analyzed. A comparison was made between those patients that met urine SIADH criteria and those who did not. ResultsA total of 126 children were included, and 23 (18.6%) of them had urine SIADH criteria. Patients in this group had a higher incidence of pneumonia and/or atelectasis on chest X-Ray (21.7% vs. 1.9%, P=.002), worse response to bronchodilator treatment with nebulized adrenaline (69,5% vs. 28,1%, P=.016), more need for respiratory assistance (high flow oxygen therapy (17.4% vs. 7.7%, p=.016), or non-invasive mechanical ventilation (13% vs. 5.8%, P=.034), and more admissions to the PICU (26.1% vs. 6.8%, P=.007). ConclusionsPatients older than one month with acute moderate bronchiolitis and urine SIADH criteria have worse clinical courses and more need for non-invasive mechanical ventilation, PICU admission, and have a higher incidence of pneumonia on chest X-ray. For that reason, it is recommended to collect a urine sample from these patients to allow an early diagnosis of SIADH, and thus early treatment of fluid and electrolyte abnormalities.

Should We Measure Fetal Omphalocele Diameter for Prediction of Perinatal Outcome?

Objective: To evaluate the fetal omphalocele diameter/abdominal circumference ratio (OD/AC) as a predictor of adverse perinatal outcome. Methods: Analysis involving 47 singleton pregnancies with fetal omphalocele, normal karyotype and absence of other major abnormalities. The OD/AC ratio was determined antenatally by ultrasound and the best cutoff for the prediction of neonatal death was determined by receiver operating characteristic curve analysis. Additional secondary outcomes included need for oral intubation in the first 24 h of life, two-step surgery or use of synthetic mesh, reoperation, parenteral feeding and need for respiratory assistance >21 days, time to first oral feed, and time to hospital discharge. Results: Fetal OD/AC did not change significantly with gestational age. Postnatal death occurred in 10 (21.3%) cases and the best cutoff for prediction was an OD/AC ratio ≥0.26. In pregnancies with the first ultrasound evaluation performed before 31 weeks' gestation and an OD/AC ≥0.26, the likelihood ratio for needing intubation in the first 24 h of life was 2.6 (95% CI: 1.2-5.7), needing two-step surgery or use of mesh was 4.9 (95% CI: 1.9-14.4), and postnatal death was 4 (95% CI: 1.9-7.5). Conclusion: A fetal ultrasound OD/AC ratio ≥0.26 is associated with increased postnatal morbidity and mortality.

PLEKHG5 deficiency leads to an intermediate form of autosomal-recessive Charcot–Marie–Tooth disease

Charcot-Marie-Tooth disease (CMT) comprises a clinically and genetically heterogeneous group of peripheral neuropathies characterized by progressive distal muscle weakness and atrophy, foot deformities and distal sensory loss. Following the analysis of two consanguineous families affected by a medium to late-onset recessive form of intermediate CMT, we identified overlapping regions of homozygosity on chromosome 1p36 with a combined maximum LOD score of 5.4. Molecular investigation of the genes from this region allowed identification of two homozygous mutations in PLEKHG5 that produce premature stop codons and are predicted to result in functional null alleles. Analysis of Plekhg5 in the mouse revealed that this gene is expressed in neurons and glial cells of the peripheral nervous system, and that knockout mice display reduced nerve conduction velocities that are comparable with those of affected individuals from both families. Interestingly, a homozygous PLEKHG5 missense mutation was previously reported in a recessive form of severe childhood onset lower motor neuron disease (LMND) leading to loss of the ability to walk and need for respiratory assistance. Together, these observations indicate that different mutations in PLEKHG5 lead to clinically diverse outcomes (intermediate CMT or LMND) affecting the function of neurons and glial cells.

Phrenic nerve conduction in the early stage of Guillain?Barre syndrome might predict the respiratory failure

To investigate whether phrenic nerve conduction in the early phase of Guillain- Barre syndrome (GBS) predicts the need for respiratory assistance during the subsequent clinical course. We performed electrophysiological examinations of conventional peripheral nerve conduction and phrenic nerve conduction for GBS patients within 14 days from the onset. We excluded patients who had already been treated with immuno-related therapy and respiratory assistance. Fifteen patients were enrolled. Three patients with the sum of phrenic nerve latency longer than 30 ms and the sum of bilateral diaphragmatic compound muscle action potential amplitude smaller than 0.3 mV required respiratory assistance after the conduction test. Our findings showed that not only delayed distal latency but also decreased amplitude may predict the need for respiratory assistance during the subsequent disease course.

Screening for Retinopathy of Prematurity: Is It Painful?

Background: Screening programmes for retinopathy of prematurity have shown to reduce unfavourable visual outcome and to be cost-effective. Following present recommendations, almost 1% of all newborn babies should therefore be screened and undergo at least one ophthalmologic examination. This is a skilled procedure that requires drug instillation and manipulation of the ocular globe with scleral indentation. The objective of this study is to describe the side effects of this ophthalmic exam with special focus on the occurrence of pain. Methods: This was an observational study with a before-after analysis where all neonates undergoing an ophthalmologic exam during a 4-month period in a third level hospital were included. CRIES pain score was determined before the exam, 5 min after and 24 h after the screening manoeuvre. Blood pressure and pulse rate were determined in addition to the mentioned measurements 30 min after the ophthalmologic examination.Minimum oxygen saturation, apnoeas, gastrointestinal side effects (like vomiting and gastric aspirates), the need for respiratory assistance or for intensive care unit admission were recorded within 24 h before and after the procedure. Results: 27 preterm neonates underwent an ophthalmologic examination and were included in the study. CRIES pain score was significantly higher 5 min after and 24 h after the screening procedure than before. This difference was also observed after stratification for birth weight and gestational age. No other study variable modified this time effect. No significant changes in blood pressure and pulse rate were shown after the ophthalmic exam. Vomiting was present in 4% of the newborns, gastric aspirates in 22% and apnoeas in 41% after the examination. Ten percent of the explored preterm babies needed increased respiratory assistance and 4% had to be transferred from the intermediate care unit to the intensive care because of severe apnoeas. Comments: An increase in pain score was shown after retinopathy of prematurity screening examination. Physiologic variable changes do not last long enough to evaluate the impact of certain procedures. Multivariate pain scores (like CRIES) should be used in everyday practice. It seems that the ophthalmologic examination in preterm babies might be painful and further studies should identify the best strategy to prevent pain during the retinopathy of prematurity screening manoeuvre.

Spinal and general anaesthesia for emergency caesarean section: Effects on neonatal Apgar score and maternal haematocrit

This is a prospective comparative study to determine the effect of the type of anaesthesia used for emergency Caesarean section on neonatal and maternal outcome. The patients were recruited into the study after being given either general or spinal anaesthesia. Neonatal outcome was assessed using Apgar scores and need for respiratory assistance at birth. Maternal outcome was assessed using the difference between pre- and post-operative packed cell volumes (PCV), need for blood transfusion and estimated blood loss. The groups were matched for pre-existing risk factors. Apgar scores at 1 and 5 minutes were found to be significantly lower for the general anaesthesia group (GA) than the spinal anaesthesia group (SA) and need for respiratory assistance was greater for the GA group. Difference between pre- and post-operative PCV and need for blood transfusion were also significantly greater in the GA group. This study confirms that the current practice of spinal anaesthesia for Caesarean section in the Lagos University Teaching Hospital is a good one, but further studies need to be done to assess other outcome variables.

Multiple trauma in elderly patients. Factors influencing outcome: importance of aggressive care

From 1978 to 1991, 126 multiply-injured patients of 65 years and over were admitted to the Department of Traumatology and Emergency Surgery of the University Hospitals of Leuven. The seriousness of the injury was evaluated using the Injury Severity Score (ISS) and the Glasgow Coma Scale (GCS). Traffic accident (57 per cent) and a simple fall at home (30 per cent) were the main causes of injury. The overall mortality rate within 6 months was 17 per cent. Multiple system organ failure (MSOF) was responsible for the fatal outcome in 48 per cent of the cases and in 71 per cent of the deaths more than 7 days after trauma. Of the survivors still living at home before injury, 78 per cent were able to go back to their normal surroundings. Survivors were compared with nonsurvivors. There was no significant difference in age or in ISS, nor in pre-existing diseases. On the other hand, the GCS was of important prognostic value, both for survival and functional recovery (P < 0.001). Also, the need for early intubation and continued ventilation were predictive of survival (P < 0.001). Nevertheless, this need for respiratory assistance was not an indication for withdrawing support as 9 per cent of the survivors also required endotracheal intubation for 5 days or longer. In our opinion, aggressive trauma care for the elderly is justified.

Use of a silastic sheet for widening the abdominal cavity in the surgical treatment of diaphragmatic hernia

Five newborns were operated on in our department by using a Silastic prosthesis to widen the abdominal cavity. The surprising postoperative course that prevented the need of recurrent surgical interventions is described. From the fifth day, some opacity appeared beneath the Silastic sheet. The wound began to contract and during 1 month all the layers of the abdominal wall regenerated. The Silastic sheet was rejected and the skin closed spontaneously. We obtained the desired result, ie, to close the abdomen and all its layers without stretching the abdominal wall, and without respiratory assistance or temporary closure of the skin and subsequent intervention for completion of the repair. We believe that in these four patients with congenital diaphragmatic hernia, this method prevented increased pressure in the abdomen and the need for respiratory assistance.

Classical heatstroke: clinical and laboratory assessment.

We reviewed the clinical and laboratory characteristics of 34 patients who had classical heatstroke during the Kansas City heat wave of 1980. The patients were elderly, predominantly black, and of low socioeconomic class. Overall mortality was 18%, with 9% of patients exhibiting severe residual neurologic deficit; 73% had full recovery. Patients with coma, temperature greater than or equal to 108 F (42.2 C), severe hypotension, coagulopathy, and need for respiratory assistance were at highest risk of death. Associated disease was common (67%), with hypertension (32%), diabetes (21%), and alcoholism (21%) being most frequent. Medications known to predispose to heatstroke were used by 56% of patients. Hematologic abnormalities were nonspecific, and clinical evidence of renal or hepatic failure was rare. Hyponatremia, hypokalemia, hypocalcemia, hypomagnesemia, hypophosphatemia, and elevated levels of creatine phosphokinase and glucose were frequent but did not correlate with outcome. The predominant arterial blood gas abnormality was metabolic acidosis or a combined metabolic acidosis and respiratory alkalosis.

PROLONGED (THERAPEUTIC) ENDOTRACHEAL INTUBATION

SUMMARY In recent years there has been an increased use of therapeutic intubation. It is especially useful in conscious patients postoperatively for periods of a day or so when the need for respiratory assistance is short-lived. It can be utilized for many days but the likelihood of laryngeal damage is probably increased, although in the individual case the shortness of the period of intubation is no guarantee of laryngeal safety. Whether the advantages of prolonged intubation outweigh the disadvantages can only be decided when the results of a series of carefully followed-up cases of prolonged intubation can be compared with those of a series of patients who have a tracheostomy inserted early in their treatment and for approximately the same length of time as the endotracheal tube. The frequency and type of laryngeal pathology suggest that therapeutic intubation should not be used for more than a few hours if there is not a strong indication for an artificial airway, but the incidence of damage is not so high as to contraindicate a prospective study comparing it with tracheostomy under apparently the same conditions.