Fr Mal Respir 1983; 11:245–246 3 Mouroux J, Riquet M, Padovani B, et al. Surgical manage- ment of thoracic manifestations in human immunodeficiency virus-positive patients: indications and results. Br J Surg 1995; 82:39 – 43 Continuous IV Sedation and Mechanical Ventilation To the Editor: We read with interest the paper by Kollef and colleagues 1 and the accompanying editorial comment. We think that paralyzed patients are a separate group and should not be included in the continuous sedation group, because those patients particularly need continuous sedation while being paralyzed. Additionally, although the paralysis effect on weaning was neutralized with the usual statistical maneu- vers, every intensive care practitioner knows that those patients are so much more difficult to wean, especially if they had been receiving steroids as well. Since the treatment allocation was not randomized, it is possible that the patients receiving continuous sedation were the ones who could not be controlled by bolus sedation, thus introducing a bias. Since no scores of the efficacy of analgesia and sedation are provided in this study, it is hard to make meaningful comparisons between the two methods of sedation. However, there are some indications that sedation and analgesia on an “as needed” basis may be inadequate. 2,3 The emotional editorial comment is very moving, but far from being practical or realistic. In our opinion, it is much more inhuman to maintain these patients conscious and aware of their traumatizing ICU experience, rather than to optimally sedate them. The use of continuous sedation avoids breakthrough discomfort and pain, as well as unnecessary extubations or line dislodgments, and it also induces “blessed” amnesia. The luxury of 1:1 nurse:patient ratio is not possible in many ICUs; the nurse has really no time for long “sedative” talks with her two patients. However, the patients benefit from the tranquilizing effects of the drugs, which also prevent many unwarranted accidents caused by patients’ restlessness and the inability of one nurse to adequately control two patients at once, even at the price of a longer weaning period. Moshe Hersch, MD Director, Intensive Care Unit Shoshana Zevin, MD Division of Internal Medicine and Clinical Pharmacology Service Shaare Zedek Medical Center Jerusalem, Israel Correspondence to: Moshe Hersch, MD, Director, Intensive Care Unit, Shaare Zedek Medical Center, P.O. Box 3235, Jerusalem 91031, Israel; e-mail: hersch@szmc.org.il References 1 Kollef MH, Levy NT, Ahrens TS, et al. The use of continuous IV sedation is associated with prolongation of mechanical ventilation. Chest 1998; 114:541–548 2 Dasta JF, Fuhrman TM, McCandles C. Patterns of prescrib- ing and administering drugs for agitation and pain in patients in a surgical intensive care unit. Crit Care Med 1994; 22:974 –980 3 Tittle M, McMillan SC. Pain and pain-related side effects in an ICU and on a surgical unit: nurses’ management. Am J Crit Care 1994; 3:25–30 The Use of Inhaled Nitric Oxide During Gas Embolism To the Editor: We read with interest the article entitled, “Venous and Arterial Gas Embolism Associated with Positive Pressure Ventilation,” by Weaver and Morris (April 1998). 1 They elegantly reported a case of massive gas embolism in a patient who died after becoming hemodynamically unstable and sustaining a right ventricular infarction. The development of right-heart failure and circulatory shock secondary to a massive increase in pulmonary vascular resistance requires prompt management, and any therapeutic attempt to improve hemodynamics is of utmost importance. Some recent experimental data consistently support the hypoth- esis that inhaled nitric oxide might be a therapeutic option in the acute management of pulmonary gas embolism. 2,3 For example, 3 ppm of inhaled nitric oxide attenuated the increase in pulmonary vascular resistance and blunted the decrease of cardiac output after a massive air embolism in dogs. 2 Similar effects were observed when nitric oxide (3 or 40 ppm) was administered during a venous air infusion in dogs. 3 In addition, although controlled trials are needed to confirm the beneficial effects of nitric oxide inhalation in patients with pulmonary embolism, 4 some authors described significantly lower pulmonary artery pressures and increases in cardiac output after nitric oxide therapy during this critical condition. 5 Even though the relevance of these findings remains to be elucidated, we believe that nitric oxide therapy could partially reverse the circulatory collapse caused by a massive gas embolism. Jose Eduardo Tanus-Santos, MD, PhD Heitor Moreno, Jr., MD, PhD Department of Pharmacology State University of Campinas Campinas, Sa ˜o Paulo, Brazil Correspondence to: Jose Eduardo Tanus-Santos, MD, PhD, De- partment of Pharmacology, Faculty of Medical Sciences, State University of Campinas, 13081-970 Campinas, Sa ˜ o Paulo, Brazil, e-mail: tanus@turing.unicamp.br References 1 Weaver LK, Morris A. Venous and arterial gas embolism associated with positive pressure ventilation. Chest 1998; 113:1132–1134 2 Tanus-Santos JE, de Nucci G. Low-dose inhaled nitric oxide attenuates hemodynamic changes following pulmonary air embolism in dogs [abstract]. Anesth Analg 1998; 86(25):S155 3 Tanus-Santos JE, Moreno Jr. H, Moreno RA, et al. Inhaled nitric oxide (NO) improves hemodynamics during a venous air infusion (VAI) in dogs. Anesthesiology 1998; 89:A452 4 Tanus-Santos JE. Inhaled nitric oxide and pulmonary embo- lism. Intensive Care Med 1998; 24:747–748 5 Capellier G, Jacques T, Balvay P, et al. Inhaled nitric oxide in patients with pulmonary embolism. Intensive Care Med 1997; 23:1089 –1092 To the Editor: We agree with Drs. Tanus-Santos and Moreno that the clinical relevance of these findings remains to be elucidated. The experimental observations in dogs cannot be extrapolated to the sick human. As Drs. Tanus-Santos and Moreno indicate, controlled trials are needed. Such trials will likely depend upon the development of methodology for early detection (eg, esophageal echo) and its widespread dissemination in a large consortium of investigative centers. The infrequent clinical recognition of massive air embolism requires that a large 1220 Communications to the Editor