*341MAJORITY OPINION
J. HARVEY HUDSON, Justice.Arlene Scott, individually and as representative of the Estate of Dorethea Scott, deceased, Jerry Scott Hubbard, James David Scott, Norman Scott, and Albert Scott, (the “Scotts”) appeal from the summary judgment granted in favor of appel-lees, Beechnut Manor, Living Centers of Texas, Inc., Living Centers of America, Inc. (“Beechnut Manor”), Vencare, Inc., Vencor Hospital, Vencor, Inc. (“Vencor”), and Robert B. Teague, M.D., on their claims of violations of the Deceptive Trade Practices-Consumer Protection Act (“DTPA”)1 and common law negligence based on res ipsa loquitur, and the dismissal of their negligence claim under the Medical Liability and Insurance Improvement Act (the “Act”). We affirm.
In 1993, Dorethea Scott suffered a stroke that left her dependent on a ventilator. On October 28, 1994, the Scott family admitted her to Beechnut Manor nursing home, where she resided in the respiratory care unit, which was staffed by Vencor. Ms. Scott was under the care of Dr. Teag-ue, who ordered constant oxygen therapy for her. The Scotts claim they were assured by the administrator that Ms. Scott would be kept on oxygen at all times. The Scotts allege Ms. Scott was taken off of oxygen on December 27, 1994, while routine maintenance was performed on the ventilator. After completing the maintenance procedure, however, the technician allegedly failed to reconnect Ms. Scott’s oxygen. Ms. Scott died later that day.
On December 6, 1996, the Scotts sued appellees alleging negligence under the Act, common law negligence based on res ipsa loquitur, and violations of the DTPA. On June 30, 1997, the trial court dismissed the Scotts’ health care liability claims under the Act, and on November 4, 1997, the trial court granted appellees’ motion for summary judgment on the Scotts’ remaining claims for common law negligence based on res ipsa loquitur and DTPA violations.
Dismissal of Claims under the Act
In their first issue, the Scotts contend the trial court erred in dismissing their claims under the Act and in overruling their motion for a new trial.
Under the Act, a claimant must provide expert reports and curricula vitae to counsel for each physician or health care provider against whom a health care liability claim is asserted. Further, the claimant must provide these reports and curricula vitae within 180 days after the filing of a health care liability claim or voluntarily nonsuit the action against the physician or healthcare provider. Tex.Rev.Civ. Stat. Ann. art. 4590i, § 13.01(d).2 If the claim*342ant fails to furnish the requisite reports and curricula vitae and fails to nonsuit the defendants, the court shall, on the motion of the affected physician or health care provider, dismiss the action with prejudice. Id. at § 13.01(e)(3).
The Scotts did not timely file expert reports and curricula vitae within 180 days of the filing of their suit as required by section 13.01(d). The time for filing the reports expired on June 4, 1997. Thus, on June 5 and 6, 1997, appellees sought a dismissal of all claims under the Act pursuant to section 13.01(e)(3). The Scotts responded on June 13, 1997, by filing the necessary reports and curricula vitae along with a “Section 13.01(f) Motion for Extension of Time.”
Section 13.01(f) provides that the “court may, for good cause shown after motion and hearing, extend any time period specified in Subsection (d) of this section for an additional 30 days.”3 The Scotts assert that their motion for extension of time was supported by uncontro-verted affidavits establishing “good cause” for the nine-day delay in filing their expert reports and curricula vitae. Thus, the Scotts argue the trial court abused its discretion in denying their motion for an extension of time as a matter of law.
It is inconsequential whether the Scotts established “good cause” because even if they made a clear showing of “good cause,” the trial court was not obliged to grant the requested extension. See Tesch v. Stroud, 28 S.W.3d 782, 787 (Tex.App.-Corpus Christi 2000, pet. denied); Knie v. Piskun, 23 S.W.3d 455, 462 (Tex.App.-Amarillo 2000, pet. denied); Schorp v. Baptist Memorial Health System, 5 S.W.3d 727, 732 (Tex.App.-San Antonio 1999, no pet.); Roberts v. Medical City Dallas Hosp., Inc., 988 S.W.2d 398, 402 (Tex.App.-Texarkana 1999, pet. denied). Accordingly, the trial court did not err in denying the Scotts’ motion for an extension of time, dismissing their suit with prejudice, and overruling their motion for new trial. The first point of error is overruled.
Summary judgment
In their second issue, the Scotts contend the trial court erred in granting summary judgment to appellees. The Scotts alleged the following causes of action in their second amended petition: (1) common-law negligence involving the doctrine of res ipsa loquitur; (2) medical malpractice under the Act, and (3) violations of the DTPA. In September 1997, the trial court granted appellees’ request for special exceptions, ordering the Scotts to replead and eliminate their DTPA claims and common law negligence claims based on art. 4590i and res ipsa loquitur. After the Scotts failed to replead, appellees moved for summary judgment on grounds that the Scotts’ claim for common law negligence based on res ipsa loquitur did not fit in one of the recognized exceptions applicable to a medical malpractice suit and the Scotts merely attempted to recast a negligence claim as a DTPA claim. On November 4, 1997, the trial court granted summary judgment on the Scotts’ remaining claims.
To prevail on a motion for summary judgment, a defendant must establish that no material fact issue exists and that it is entitled to judgment as a matter of law. Rhone-Poulenc, Inc. v. Steel, 997 *343S.W.2d 217, 222 (Tex.1999). Once the defendant establishes that no genuine issue of material fact exists regarding an element of the plaintiffs claim, the plaintiff must present competent summary judgment evidence raising a fact issue on that element. Guest v. Cochran, 998 S.W.2d 897, 401 (Tex.App.-Houston [14th Dist.] 1999, no pet.). In conducting our review of the summary judgment, we take as true all evidence favorable to the nonmovants, and make all reasonable inferences in the nonmovant’s favor. KPMG Peat Marwick v. Harrison County Hous. Fin. Corp., 988 S.W.2d 746, 748 (Tex.1999). A defendant, as movant, is entitled to summary judgment if it either disproves at least one essential element of each of the plaintiffs causes of action or establishes all the elements of an affirmative defense. American Tobacco Co. v. Grinnell, 951 S.W.2d 420, 425 (Tex.1997). If the trial court sustains a defendant’s special exception that the plaintiff failed to state a cause of action and the plaintiff fails to replead when ordered to do so, summary judgment may properly be granted. Haase v. Glazner, 62 S.W.3d 795, 800 (Tex.2001); Sumerlin v. Houston Title Co., 808 S.W.2d 724, 726 (Tex.App.-Houston [14th Dist.] 1991, writ denied).
Res Ipsa Loquitur
Res ipsa loquitur is applicable when the following two circumstances are present: (1) the character of the accident is such that it would not ordinarily occur in the absence of negligence, and (2) the instrumentality causing the injury is shown to have been under the management and control of the defendant. Haddock v. Arnspiger, 793 S.W.2d 948, 950 (Tex.1990). Res ipsa loquitur is a rule of evidence by which negligence many be inferred by the jury; it is not a separate cause of action from negligence. Id.
With regard to medical malpractice cases, res ipsa loquitur applies only to those cases to which it had been applied as of August 29, 1977, the effective date of the Act. Tex.Rev.Civ. Stat. Ann. art. 4590i, § 7.01.4 Res ipsa loquitur is inapplicable to medical malpractice cases except where the nature of the alleged malpractice and injuries are within the common knowledge of laymen, requiring no expert testimony. Haddock, 793 S.W.2d at 951. The three recognized areas wherein res ipsa loquitur is applicable to medical malpractice claims are negligence in the use of mechanical instruments, operating on the wrong portion of the body, and leaving surgical instruments or sponges within the body. Id.
However, not every medical malpractice case involving the use of a mechanical instrument permits the application of res ipsa loquitur. Id. Res ipsa loquitur is not applicable to those cases in which the use of the mechanical instrument is not a matter within the common knowledge of laymen. Id.
Although the Seotts allege the negligent use of a mechanical instrument, i.e., the ventilator, we conclude the use of the instrument does not fall plainly within the common knowledge of a lay person. Dr. Teague claimed in his affidavit that Ms. *344Scott’s death was caused by respiratory failure, due to, or as the likely consequence of, a stroke. Dr. Teague further explained that Ms. Scott was “ventilator dependent, and required tube feeding, continuous ne-bulizer treatments, and trach care.” Even if it is common knowledge that a ventilator assists a patient to breathe, we find lay persons require the assistance of expert testimony before they can presume that an injury is due to the negligent misuse of such an instrument.
Because the Scotts have not alleged facts falling within the narrow exception for res ipsa loquitur in a medical malpractice case, the trial court did not err in granting summary judgment on the grounds that the negligence claim relying on res ipsa loquitur fails as a matter of law.
DTPA
The DTPA does not apply to health care providers with respect to claims for damages for personal injury or death resulting, or alleged to have resulted, from negligence. Tex.Rev.Civ. Stat. Ann. art. 4590i, § 12.01(a).5 Section 12.01(a) precludes a DTPA claim against a physician if it is based on a breach of the accepted standard of medical care. Sorok-olit v. Rhodes, 889 S.W.2d 239, 242 (Tex. 1994). However, if the alleged DTPA claim is not based on the physician’s breach of the accepted standard of medical care, such DTPA claim is not precluded by section 12.01(a). Id. A claim that a physician or health care provider was negligent may not be recast as a DTPA claim to avoid the standards set forth in the Act. Id. To determine whether a DTPA claim is based on negligence, the court should focus solely on the plaintiffs pleadings. MacGregor Med. Ass’n v. Campbell, 985 S.W.2d 38, 41 (Tex.1998). Thus, the underlying nature of a claim determines whether section 12.01(a) bars a claim for violation of the DTPA. Id.; Sorokolit, 889 5.W.2d at 242. A health care liability claim is defined by the Act as “a cause of action against a health care provider or physician for treatment, lack of treatment, or other claimed departure from accepted standards of medical care or health care or safety which proximately results in injury to or death of the patient, whether the patient’s claim or cause of action sounds in tort or contract.” Tex.Rev.Civ. Stat. Ann. art. 4590i, § 1.03(a)(4).6 Section 12.01(a) does not preclude DTPA actions for knowing misrepresentation or breach of express warranty in cases in which a physician or health care provider warrants a particular result. Sorokolit, 889 S.W.2d at 242.
With respect to their DTPA claim, the Scotts alleged:
*345Plaintiffs would show that Defendants expressly warranted and represented that Ms. Scott would be kept on oxygen, but Defendants breached that express warranty and representation and allowed Ms. Scott to go off oxygen, or inadequate oxygen, all to her detriment. This representation was “knowing” by defendants and the warranty in question was a warranty that “warrants a particular result”, namely that Ms. Scott would be kept on oxygen. The breach of such warranty and the knowing misrepresentation alleged just above constituted deceptive trade practices, all of which were a proximate cause of the actual damages hereinafter alleged.
In Mulligan v. Beverly Enters.-Tex., Inc., we found similar claims were essentially negligence-based claims rather than DTPA claims. 954 S.W.2d 881, 884 (Tex.App.-Houston [14th Dist.] 1997, no pet.). In that case, Mulligan alleged that the nursing home made representations about the services her aunt was to receive and express warranties about the care to be provided. Id. However, we determined that each alleged warranty or representation went to the level of care provided by the nursing home to the aunt. Id. We noted that Mulligan did not allege that services were entirely withheld from her aunt, but that the services provided were not of a level she found acceptable or in compliance with normal standards. Id. We held a conclusion that the representations and warranties were breached required a determination of whether the nursing home failed to meet the standard of medical care and, therefore, Mulligan was attempting to recast her negligence claim as a DTPA claim. Id.
In Waters v. Del-Ky, Inc., the plaintiff sued the defendant nursing home for breach of an express warranty that the nursing home would provide specific services when it had not. 844 S.W.2d 250, 258 (Tex.App.-Dallas 1992, no writ). The plaintiff alleged that the nursing home breached express warranties of the physical and medical care it would provide, that its personnel would provide adequate and proper supervised care, that it would comply with all standards of participation promulgated by the Texas Department of Health, and that it would correct the deficiencies in care. Id. The court of appeals determined that the plaintiffs claims were claims for lack of treatment or other claimed departure from accepted standards of medical care, health care, or safety. Id.
Similarly, we find the Scotts’ DTPA claim that appellees “expressly warranted and represented that Ms. Scott would be kept on oxygen, but that [appellees] breached that express warranty and representation and allowed Ms. Scott to go off oxygen, or inadequate oxygen, all to her detriment,” is nothing more than an impermissible attempt to recast a negligence claim as a DTPA claim. Their claim is one concerning a departure from accepted standards of medical care, health care, or safety. There is no claim of guaranteed results in the care appellees would provide to Ms. Scott. Any determination that the representations and warranties were breached necessarily would require a determination of whether appellees failed to meet the standard of medical care for Ms. Scott. We conclude the trial court properly granted summary judgment on the ground that the Act precluded the Scotts from casting their negligence claim as a DTPA claim. The Scotts’ second issue is overruled.
Accordingly, the judgment of the trial court is affirmed.
FROST, J., concurring.
. See Tex. Bus. & Com.Code Ann. §§ 17.41-.63 (Vernon 2002 & Supp.2004-05).
. Section 13.01 of the Act was formerly found at Tex.Rev.Civ. Stat. Ann. art. 4590i, § 13.01. See Act of May 5, 1995, 74th Leg., R.S., ch. 140, § 1, 1995 Tex. Gen. Laws 985, 985-87, repealed by Act of June 2, 2003, 78th Leg., R.S., ch. 204, § 10.09, 2003 Tex. Gen. Laws 847, 887 (current version found at Tex. Civ. Prac. & Rem.Code Ann. § 74.351 (Vernon Supp. 2004 — 05)). The former statute continues in effect for cases filed before September 1, 2003. Because this case was filed in 1996, the former statute — Tex. Rev. Civ. Stat. Ann. art. 4590Í — is applicable and all references are to the former statute. Section 13.01(d) states:
Not later than the later of the 180th day after the date on which a health care liability claim is filed or the last day of any extended period established under Subsection (f) or (h) of this section, the claimant shall, for each physician or health care provider against whom a claim is asserted:
(1) furnish to counsel for each physician or health care provider one or more expert *342reports, with a curriculum vitae of each expert listed in the report; or
(2) voluntarily nonsuit the action against the physician or health care provider.
Id.
. Tex.Rev.Civ. Stat. Ann. art. 4590i, § 13.01(f).
. Section 7.01 of the Act was formerly found at Tex.Rev.Civ. Stat. Ann. art. 4590i, § 7.01. See Act of June 16, 1997, 65th Leg., R.S., ch. 817, § 7.01, 1977 Tex. Gen. Laws 2039, 2050, repealed by Act of June 2, 2003, 78th Leg., R.S., ch. 204, § 10.09, 2003 Tex. Gen. Laws 847, 887 (current version found at Tex. Civ. Prac. & Rem.Code Ann. § 74.201 (Vernon Supp.2004-05)). Section 7.01 states that "[t]he common-law doctrine of res ipsa loquitur shall only apply to health care liability claims against health care providers or physicians in those cases to which it has been applied by the appellate courts of this state as of the effective date of this subchapter.” Id.
. Section 12.01 of the Act was formerly found at Tex.Rev.Civ. Stat. Ann. § 12.01. See Act of June 16, 1977, 65th Leg., R.S., ch. 817, § 12.01, 1977 Tex. Gen. Laws 2039, 2053, repealed by Act of June 2, 2003, 78th Leg., R.S., ch. 204, § 10.09, 2003 Tex. Gen. Laws 847, 887 (current version found at Tex Civ. Prac. & Rem.Code Ann. § 74.004 (Vernon Supp. 2004-05)). Section 12.01(a) provides that ''[njotwithstanding any other law, no provisions of sections 17.41-17.63, Business & Commerce Code, shall apply to physicians or health care providers as defined in Section 1.03(a) of this Act, with respect to claims for damages for personal injury or death result-tag, or alleged to have resulted, from negligence on the part of any physician or health care provider.” Id.
. Section 1.03(a)(4) of the Act was formerly found at Tex.Rev.Civ. Stat. Ann. § 1.03(a)(4). See Act of June 16, 1977, 65th Leg., R.S., ch. 817, § 12.01, 1977 Tex. Gen. Laws 2039, 2041, repealed by Act of June 2, 2003, 78th Leg., R.S., ch. 204, § 10.09, 2003 Tex. Gen. Laws 847, 887 (current version found at Tex. Civ. Prac. & Rem.Code Ann. § 74.001(a)(13) (Vernon Supp.2004-05)).